diff --git a/aegisub/build/Aegisub/Aegisub.vcxproj b/aegisub/build/Aegisub/Aegisub.vcxproj
index 8cf1ebd6c..c58fc3417 100644
--- a/aegisub/build/Aegisub/Aegisub.vcxproj
+++ b/aegisub/build/Aegisub/Aegisub.vcxproj
@@ -200,6 +200,7 @@
+
@@ -394,6 +395,10 @@
+
+ NotUsing
+
+
diff --git a/aegisub/build/Aegisub/Aegisub.vcxproj.filters b/aegisub/build/Aegisub/Aegisub.vcxproj.filters
index 24222fdcd..d4a250303 100644
--- a/aegisub/build/Aegisub/Aegisub.vcxproj.filters
+++ b/aegisub/build/Aegisub/Aegisub.vcxproj.filters
@@ -690,6 +690,9 @@
Automation\Lua
+
+ Automation\Lua
+
@@ -1241,6 +1244,9 @@
Automation\Lua
+
+ Automation\Lua
+
diff --git a/aegisub/src/Makefile b/aegisub/src/Makefile
index 008975596..7eb976875 100644
--- a/aegisub/src/Makefile
+++ b/aegisub/src/Makefile
@@ -200,6 +200,7 @@ SRC += \
hotkey_data_view_model.cpp \
initial_line_state.cpp \
kana_table.cpp \
+ lpeg.c \
main.cpp \
menu.cpp \
mkv_wrap.cpp \
diff --git a/aegisub/src/auto4_lua.cpp b/aegisub/src/auto4_lua.cpp
index 3d32bc51d..bd772d13b 100644
--- a/aegisub/src/auto4_lua.cpp
+++ b/aegisub/src/auto4_lua.cpp
@@ -193,6 +193,8 @@ namespace {
}
}
+extern "C" int luaopen_lpeg (lua_State *L);
+
namespace Automation4 {
int regex_init(lua_State *L);
@@ -220,12 +222,13 @@ namespace Automation4 {
// register standard libs
push_value(L, luaopen_base); lua_call(L, 0, 0);
+ push_value(L, luaopen_io); lua_call(L, 0, 0);
+ push_value(L, luaopen_lpeg); lua_call(L, 0, 0);
+ push_value(L, luaopen_math); lua_call(L, 0, 0);
+ push_value(L, luaopen_os); lua_call(L, 0, 0);
push_value(L, luaopen_package); lua_call(L, 0, 0);
push_value(L, luaopen_string); lua_call(L, 0, 0);
push_value(L, luaopen_table); lua_call(L, 0, 0);
- push_value(L, luaopen_math); lua_call(L, 0, 0);
- push_value(L, luaopen_io); lua_call(L, 0, 0);
- push_value(L, luaopen_os); lua_call(L, 0, 0);
_stackcheck.check_stack(0);
// dofile and loadfile are replaced with include
diff --git a/aegisub/src/lpeg.c b/aegisub/src/lpeg.c
new file mode 100644
index 000000000..fe4661947
--- /dev/null
+++ b/aegisub/src/lpeg.c
@@ -0,0 +1,2400 @@
+/*
+** $Id: lpeg.c,v 1.112 2010/11/03 17:07:50 roberto Exp $
+** LPeg - PEG pattern matching for Lua
+** Copyright 2007, Lua.org & PUC-Rio (see 'lpeg.html' for license)
+** written by Roberto Ierusalimschy
+*/
+
+
+#include
+#include
+#include
+#include
+#include
+
+#include "lua.h"
+#include "lauxlib.h"
+
+#include "lpeg.h"
+
+
+#define VERSION "0.10"
+#define PATTERN_T "lpeg-pattern"
+#define MAXSTACKIDX "lpeg-maxstack"
+
+
+/*
+** compatibility with Lua 5.2
+*/
+#if (LUA_VERSION_NUM == 502)
+
+#undef lua_equal
+#define lua_equal(L,idx1,idx2) lua_compare(L,(idx1),(idx2),LUA_OPEQ)
+
+#undef lua_getfenv
+#define lua_getfenv lua_getuservalue
+#undef lua_setfenv
+#define lua_setfenv lua_setuservalue
+
+#undef lua_objlen
+#define lua_objlen lua_rawlen
+
+#undef luaL_register
+#define luaL_register(L,n,f) \
+ { if ((n) == NULL) luaL_setfuncs(L,f,0); else luaL_newlib(L,f); }
+
+#endif
+
+
+
+/* initial size for call/backtrack stack */
+#define INITBACK 100
+
+/* default maximum size for call/backtrack stack */
+#define MAXBACK INITBACK
+
+/* size for call/backtrack stack for verifier */
+#define MAXBACKVER 200
+
+/* initial size for capture's list */
+#define INITCAPSIZE 32
+
+
+/* index, on Lua stack, for subject */
+#define SUBJIDX 2
+
+/* number of fixed arguments to 'match' (before capture arguments) */
+#define FIXEDARGS 3
+
+/* index, on Lua stack, for substitution value cache */
+#define subscache(cs) ((cs)->ptop + 1)
+
+/* index, on Lua stack, for capture list */
+#define caplistidx(ptop) ((ptop) + 2)
+
+/* index, on Lua stack, for pattern's fenv */
+#define penvidx(ptop) ((ptop) + 3)
+
+/* index, on Lua stack, for backtracking stack */
+#define stackidx(ptop) ((ptop) + 4)
+
+
+
+typedef unsigned char byte;
+
+
+#define CHARSETSIZE ((UCHAR_MAX/CHAR_BIT) + 1)
+
+
+typedef byte Charset[CHARSETSIZE];
+
+
+/* Virtual Machine's instructions */
+typedef enum Opcode {
+ IAny, IChar, ISet, ISpan,
+ IBack,
+ IRet, IEnd,
+ IChoice, IJmp, ICall, IOpenCall,
+ ICommit, IPartialCommit, IBackCommit, IFailTwice, IFail, IGiveup,
+ IFunc,
+ IFullCapture, IEmptyCapture, IEmptyCaptureIdx,
+ IOpenCapture, ICloseCapture, ICloseRunTime
+} Opcode;
+
+
+#define ISJMP 0x1
+#define ISCHECK 0x2
+#define ISFIXCHECK 0x4
+#define ISNOFAIL 0x8
+#define ISCAPTURE 0x10
+#define ISMOVABLE 0x20
+#define ISFENVOFF 0x40
+
+static const int opproperties[] = {
+ /* IAny */ ISCHECK | ISFIXCHECK | ISJMP,
+ /* IChar */ ISCHECK | ISFIXCHECK | ISJMP,
+ /* ISet */ ISCHECK | ISFIXCHECK | ISJMP,
+ /* ISpan */ ISNOFAIL,
+ /* IBack */ 0,
+ /* IRet */ 0,
+ /* IEnd */ 0,
+ /* IChoice */ ISJMP,
+ /* IJmp */ ISJMP | ISNOFAIL,
+ /* ICall */ ISJMP,
+ /* IOpenCall */ ISFENVOFF,
+ /* ICommit */ ISJMP,
+ /* IPartialCommit */ ISJMP,
+ /* IBackCommit */ ISJMP,
+ /* IFailTwice */ 0,
+ /* IFail */ 0,
+ /* IGiveup */ 0,
+ /* IFunc */ ISCHECK | ISJMP,
+ /* IFullCapture */ ISCAPTURE | ISNOFAIL | ISFENVOFF,
+ /* IEmptyCapture */ ISCAPTURE | ISNOFAIL | ISMOVABLE,
+ /* IEmptyCaptureIdx */ISCAPTURE | ISNOFAIL | ISMOVABLE | ISFENVOFF,
+ /* IOpenCapture */ ISCAPTURE | ISNOFAIL | ISMOVABLE | ISFENVOFF,
+ /* ICloseCapture */ ISCAPTURE | ISNOFAIL | ISMOVABLE | ISFENVOFF,
+ /* ICloseRunTime */ ISCAPTURE | ISFENVOFF
+};
+
+
+typedef union Instruction {
+ struct Inst {
+ byte code;
+ byte aux;
+ short offset;
+ } i;
+ PattFunc f;
+ int iv;
+ byte buff[1];
+} Instruction;
+
+static const Instruction giveup = {{IGiveup, 0, 0}};
+
+#define getkind(op) ((op)->i.aux & 0xF)
+#define getoff(op) (((op)->i.aux >> 4) & 0xF)
+
+#define dest(p,x) ((x) + ((p)+(x))->i.offset)
+
+#define MAXOFF 0xF
+#define MAXAUX 0xFF
+
+/* maximum size (in elements) for a pattern */
+#define MAXPATTSIZE (SHRT_MAX - 10)
+
+
+#define isprop(op,p) (opproperties[(op)->i.code] & (p))
+#define isjmp(op) (isprop(op, ISJMP) && (op)->i.offset != 0)
+#define iscapture(op) isprop(op, ISCAPTURE)
+#define ischeck(op) (isprop(op, ISCHECK) && (op)->i.offset == 0)
+#define isfixcheck(op) (isprop(op, ISFIXCHECK) && (op)->i.offset == 0)
+#define istest(op) (isprop(op, ISCHECK) && (op)->i.offset != 0)
+#define isnofail(op) isprop(op, ISNOFAIL)
+#define ismovable(op) isprop(op, ISMOVABLE)
+#define isfenvoff(op) isprop(op, ISFENVOFF)
+
+
+/* kinds of captures */
+typedef enum CapKind {
+ Cclose, Cposition, Cconst, Cbackref, Carg, Csimple, Ctable, Cfunction,
+ Cquery, Cstring, Csubst, Cfold, Cruntime, Cgroup
+} CapKind;
+
+#define iscapnosize(k) ((k) == Cposition || (k) == Cconst)
+
+
+typedef struct Capture {
+ const char *s; /* position */
+ short idx;
+ byte kind;
+ byte siz;
+} Capture;
+
+
+/* size (in elements) for an instruction plus extra l bytes */
+#define instsize(l) (((l) + sizeof(Instruction) - 1)/sizeof(Instruction) + 1)
+
+
+/* size (in elements) for a ISet instruction */
+#define CHARSETINSTSIZE instsize(CHARSETSIZE)
+
+/* size (in elements) for a IFunc instruction */
+#define funcinstsize(p) ((p)->i.aux + 2)
+
+
+#define loopset(v,b) { int v; for (v = 0; v < CHARSETSIZE; v++) b; }
+
+
+#define testchar(st,c) (((int)(st)[((c) >> 3)] & (1 << ((c) & 7))))
+#define setchar(st,c) ((st)[(c) >> 3] |= (1 << ((c) & 7)))
+
+
+
+static int sizei (const Instruction *i) {
+ switch((Opcode)i->i.code) {
+ case ISet: case ISpan: return CHARSETINSTSIZE;
+ case IFunc: return funcinstsize(i);
+ default: return 1;
+ }
+}
+
+
+static const char *val2str (lua_State *L, int idx) {
+ const char *k = lua_tostring(L, idx);
+ if (k != NULL)
+ return lua_pushfstring(L, "rule '%s'", k);
+ else
+ return lua_pushfstring(L, "rule ", luaL_typename(L, idx));
+}
+
+
+static int getposition (lua_State *L, int t, int i) {
+ int res;
+ lua_getfenv(L, -1);
+ lua_rawgeti(L, -1, i); /* get key from pattern's environment */
+ lua_gettable(L, t); /* get position from positions table */
+ res = lua_tointeger(L, -1);
+ if (res == 0) { /* key has no registered position? */
+ lua_rawgeti(L, -2, i); /* get key again */
+ return luaL_error(L, "%s is not defined in given grammar", val2str(L, -1));
+ }
+ lua_pop(L, 2); /* remove environment and position */
+ return res;
+}
+
+
+/*
+** {======================================================
+** Printing patterns
+** =======================================================
+*/
+
+
+static void printcharset (const Charset st) {
+ int i;
+ printf("[");
+ for (i = 0; i <= UCHAR_MAX; i++) {
+ int first = i;
+ while (testchar(st, i) && i <= UCHAR_MAX) i++;
+ if (i - 1 == first) /* unary range? */
+ printf("(%02x)", first);
+ else if (i - 1 > first) /* non-empty range? */
+ printf("(%02x-%02x)", first, i - 1);
+ }
+ printf("]");
+}
+
+
+static void printcapkind (int kind) {
+ const char *const modes[] = {
+ "close", "position", "constant", "backref",
+ "argument", "simple", "table", "function",
+ "query", "string", "substitution", "fold",
+ "runtime", "group"};
+ printf("%s", modes[kind]);
+}
+
+
+static void printjmp (const Instruction *op, const Instruction *p) {
+ printf("-> ");
+ if (p->i.offset == 0) printf("FAIL");
+ else printf("%d", (int)(dest(0, p) - op));
+}
+
+
+static void printinst (const Instruction *op, const Instruction *p) {
+ const char *const names[] = {
+ "any", "char", "set", "span", "back",
+ "ret", "end",
+ "choice", "jmp", "call", "open_call",
+ "commit", "partial_commit", "back_commit", "failtwice", "fail", "giveup",
+ "func",
+ "fullcapture", "emptycapture", "emptycaptureidx", "opencapture",
+ "closecapture", "closeruntime"
+ };
+ printf("%02ld: %s ", (long)(p - op), names[p->i.code]);
+ switch ((Opcode)p->i.code) {
+ case IChar: {
+ printf("'%c'", p->i.aux);
+ printjmp(op, p);
+ break;
+ }
+ case IAny: {
+ printf("* %d", p->i.aux);
+ printjmp(op, p);
+ break;
+ }
+ case IFullCapture: case IOpenCapture:
+ case IEmptyCapture: case IEmptyCaptureIdx:
+ case ICloseCapture: case ICloseRunTime: {
+ printcapkind(getkind(p));
+ printf("(n = %d) (off = %d)", getoff(p), p->i.offset);
+ break;
+ }
+ case ISet: {
+ printcharset((p+1)->buff);
+ printjmp(op, p);
+ break;
+ }
+ case ISpan: {
+ printcharset((p+1)->buff);
+ break;
+ }
+ case IOpenCall: {
+ printf("-> %d", p->i.offset);
+ break;
+ }
+ case IChoice: {
+ printjmp(op, p);
+ printf(" (%d)", p->i.aux);
+ break;
+ }
+ case IJmp: case ICall: case ICommit:
+ case IPartialCommit: case IBackCommit: {
+ printjmp(op, p);
+ break;
+ }
+ default: break;
+ }
+ printf("\n");
+}
+
+
+static void printpatt (Instruction *p) {
+ Instruction *op = p;
+ for (;;) {
+ printinst(op, p);
+ if ((Opcode)p->i.code == IEnd) break;
+ p += sizei(p);
+ }
+}
+
+
+static void printcap (Capture *cap) {
+ printcapkind(cap->kind);
+ printf(" (idx: %d - size: %d) -> %p\n", cap->idx, cap->siz, cap->s);
+}
+
+
+static void printcaplist (Capture *cap) {
+ for (; cap->s; cap++) printcap(cap);
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Virtual Machine
+** =======================================================
+*/
+
+
+typedef struct Stack {
+ const char *s;
+ const Instruction *p;
+ int caplevel;
+} Stack;
+
+
+#define getstackbase(L, ptop) ((Stack *)lua_touserdata(L, stackidx(ptop)))
+
+
+static int runtimecap (lua_State *L, Capture *close, Capture *ocap,
+ const char *o, const char *s, int ptop);
+
+
+static Capture *doublecap (lua_State *L, Capture *cap, int captop, int ptop) {
+ Capture *newc;
+ if (captop >= INT_MAX/((int)sizeof(Capture) * 2))
+ luaL_error(L, "too many captures");
+ newc = (Capture *)lua_newuserdata(L, captop * 2 * sizeof(Capture));
+ memcpy(newc, cap, captop * sizeof(Capture));
+ lua_replace(L, caplistidx(ptop));
+ return newc;
+}
+
+
+static Stack *doublestack (lua_State *L, Stack **stacklimit, int ptop) {
+ Stack *stack = getstackbase(L, ptop);
+ Stack *newstack;
+ int n = *stacklimit - stack;
+ int max, newn;
+ lua_getfield(L, LUA_REGISTRYINDEX, MAXSTACKIDX);
+ max = lua_tointeger(L, -1);
+ lua_pop(L, 1);
+ if (n >= max)
+ luaL_error(L, "too many pending calls/choices");
+ newn = 2*n; if (newn > max) newn = max;
+ newstack = (Stack *)lua_newuserdata(L, newn * sizeof(Stack));
+ memcpy(newstack, stack, n * sizeof(Stack));
+ lua_replace(L, stackidx(ptop));
+ *stacklimit = newstack + newn;
+ return newstack + n;
+
+}
+
+
+static void adddyncaptures (const char *s, Capture *base, int n, int fd) {
+ int i;
+ assert(base[0].kind == Cruntime && base[0].siz == 0);
+ base[0].idx = fd; /* first returned capture */
+ for (i = 1; i < n; i++) { /* add extra captures */
+ base[i].siz = 1; /* mark it as closed */
+ base[i].s = s;
+ base[i].kind = Cruntime;
+ base[i].idx = fd + i; /* stack index */
+ }
+ base[n].kind = Cclose; /* add closing entry */
+ base[n].siz = 1;
+ base[n].s = s;
+}
+
+
+#define condfailed(p) { int f = p->i.offset; if (f) p+=f; else goto fail; }
+
+static const char *match (lua_State *L,
+ const char *o, const char *s, const char *e,
+ Instruction *op, Capture *capture, int ptop) {
+ Stack stackbase[INITBACK];
+ Stack *stacklimit = stackbase + INITBACK;
+ Stack *stack = stackbase; /* point to first empty slot in stack */
+ int capsize = INITCAPSIZE;
+ int captop = 0; /* point to first empty slot in captures */
+ const Instruction *p = op;
+ stack->p = &giveup; stack->s = s; stack->caplevel = 0; stack++;
+ lua_pushlightuserdata(L, stackbase);
+ for (;;) {
+#if defined(DEBUG)
+ printf("s: |%s| stck: %d c: %d ",
+ s, stack - getstackbase(L, ptop), captop);
+ printinst(op, p);
+#endif
+ switch ((Opcode)p->i.code) {
+ case IEnd: {
+ assert(stack == getstackbase(L, ptop) + 1);
+ capture[captop].kind = Cclose;
+ capture[captop].s = NULL;
+ return s;
+ }
+ case IGiveup: {
+ assert(stack == getstackbase(L, ptop));
+ return NULL;
+ }
+ case IRet: {
+ assert(stack > getstackbase(L, ptop) && (stack - 1)->s == NULL);
+ p = (--stack)->p;
+ continue;
+ }
+ case IAny: {
+ int n = p->i.aux;
+ if (n <= e - s) { p++; s += n; }
+ else condfailed(p);
+ continue;
+ }
+ case IChar: {
+ if ((byte)*s == p->i.aux && s < e) { p++; s++; }
+ else condfailed(p);
+ continue;
+ }
+ case ISet: {
+ int c = (byte)*s;
+ if (testchar((p+1)->buff, c) && s < e)
+ { p += CHARSETINSTSIZE; s++; }
+ else condfailed(p);
+ continue;
+ }
+ case IBack: {
+ int n = p->i.aux;
+ if (n > s - o) goto fail;
+ s -= n; p++;
+ continue;
+ }
+ case ISpan: {
+ for (; s < e; s++) {
+ int c = (byte)*s;
+ if (!testchar((p+1)->buff, c)) break;
+ }
+ p += CHARSETINSTSIZE;
+ continue;
+ }
+ case IFunc: {
+ const char *r = (p+1)->f(s, e, o, (p+2)->buff);
+ if (r != NULL) { s = r; p += funcinstsize(p); }
+ else condfailed(p);
+ continue;
+ }
+ case IJmp: {
+ p += p->i.offset;
+ continue;
+ }
+ case IChoice: {
+ if (stack == stacklimit)
+ stack = doublestack(L, &stacklimit, ptop);
+ stack->p = dest(0, p);
+ stack->s = s - p->i.aux;
+ stack->caplevel = captop;
+ stack++;
+ p++;
+ continue;
+ }
+ case ICall: {
+ if (stack == stacklimit)
+ stack = doublestack(L, &stacklimit, ptop);
+ stack->s = NULL;
+ stack->p = p + 1; /* save return address */
+ stack++;
+ p += p->i.offset;
+ continue;
+ }
+ case ICommit: {
+ assert(stack > getstackbase(L, ptop) && (stack - 1)->s != NULL);
+ stack--;
+ p += p->i.offset;
+ continue;
+ }
+ case IPartialCommit: {
+ assert(stack > getstackbase(L, ptop) && (stack - 1)->s != NULL);
+ (stack - 1)->s = s;
+ (stack - 1)->caplevel = captop;
+ p += p->i.offset;
+ continue;
+ }
+ case IBackCommit: {
+ assert(stack > getstackbase(L, ptop) && (stack - 1)->s != NULL);
+ s = (--stack)->s;
+ captop = stack->caplevel;
+ p += p->i.offset;
+ continue;
+ }
+ case IFailTwice:
+ assert(stack > getstackbase(L, ptop));
+ stack--;
+ /* go through */
+ case IFail:
+ fail: { /* pattern failed: try to backtrack */
+ do { /* remove pending calls */
+ assert(stack > getstackbase(L, ptop));
+ s = (--stack)->s;
+ } while (s == NULL);
+ captop = stack->caplevel;
+ p = stack->p;
+ continue;
+ }
+ case ICloseRunTime: {
+ int fr = lua_gettop(L) + 1; /* stack index of first result */
+ int ncap = runtimecap(L, capture + captop, capture, o, s, ptop);
+ lua_Integer res = lua_tointeger(L, fr) - 1; /* offset */
+ int n = lua_gettop(L) - fr; /* number of new captures */
+ if (res == -1) { /* may not be a number */
+ if (!lua_toboolean(L, fr)) { /* false value? */
+ lua_settop(L, fr - 1); /* remove results */
+ goto fail; /* and fail */
+ }
+ else if (lua_isboolean(L, fr)) /* true? */
+ res = s - o; /* keep current position */
+ }
+ if (res < s - o || res > e - o)
+ luaL_error(L, "invalid position returned by match-time capture");
+ s = o + res; /* update current position */
+ captop -= ncap; /* remove nested captures */
+ lua_remove(L, fr); /* remove first result (offset) */
+ if (n > 0) { /* captures? */
+ if ((captop += n + 1) >= capsize) {
+ capture = doublecap(L, capture, captop, ptop);
+ capsize = 2 * captop;
+ }
+ adddyncaptures(s, capture + captop - n - 1, n, fr);
+ }
+ p++;
+ continue;
+ }
+ case ICloseCapture: {
+ const char *s1 = s - getoff(p);
+ assert(captop > 0);
+ if (capture[captop - 1].siz == 0 &&
+ s1 - capture[captop - 1].s < UCHAR_MAX) {
+ capture[captop - 1].siz = s1 - capture[captop - 1].s + 1;
+ p++;
+ continue;
+ }
+ else {
+ capture[captop].siz = 1; /* mark entry as closed */
+ goto capture;
+ }
+ }
+ case IEmptyCapture: case IEmptyCaptureIdx:
+ capture[captop].siz = 1; /* mark entry as closed */
+ goto capture;
+ case IOpenCapture:
+ capture[captop].siz = 0; /* mark entry as open */
+ goto capture;
+ case IFullCapture:
+ capture[captop].siz = getoff(p) + 1; /* save capture size */
+ capture: {
+ capture[captop].s = s - getoff(p);
+ capture[captop].idx = p->i.offset;
+ capture[captop].kind = getkind(p);
+ if (++captop >= capsize) {
+ capture = doublecap(L, capture, captop, ptop);
+ capsize = 2 * captop;
+ }
+ p++;
+ continue;
+ }
+ case IOpenCall: {
+ lua_rawgeti(L, penvidx(ptop), p->i.offset);
+ luaL_error(L, "reference to %s outside a grammar", val2str(L, -1));
+ }
+ default: assert(0); return NULL;
+ }
+ }
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Verifier
+** =======================================================
+*/
+
+
+/*
+** check whether pattern may go from 'p' to 'e' without consuming any
+** input. Raises an error if it detects a left recursion. 'op' points
+** the beginning of the pattern. If pattern belongs to a grammar,
+** 'rule' is the stack index where is its corresponding key (only for
+** error messages) and 'posttable' is the stack index with a table
+** mapping rule keys to the position of their code in the pattern.
+*/
+static int verify (lua_State *L, Instruction *op, const Instruction *p,
+ Instruction *e, int postable, int rule) {
+ static const char dummy[] = "";
+ Stack back[MAXBACKVER];
+ int backtop = 0; /* point to first empty slot in back */
+ while (p != e) {
+ switch ((Opcode)p->i.code) {
+ case IRet: {
+ p = back[--backtop].p;
+ continue;
+ }
+ case IChoice: {
+ if (backtop >= MAXBACKVER)
+ return luaL_error(L, "too many pending calls/choices");
+ back[backtop].p = dest(0, p);
+ back[backtop++].s = dummy;
+ p++;
+ continue;
+ }
+ case ICall: {
+ assert((p + 1)->i.code != IRet); /* no tail call */
+ if (backtop >= MAXBACKVER)
+ return luaL_error(L, "too many pending calls/choices");
+ back[backtop].s = NULL;
+ back[backtop++].p = p + 1;
+ goto dojmp;
+ }
+ case IOpenCall: {
+ int i;
+ if (postable == 0) /* grammar still not fixed? */
+ goto fail; /* to be verified later */
+ for (i = 0; i < backtop; i++) {
+ if (back[i].s == NULL && back[i].p == p + 1)
+ return luaL_error(L, "%s is left recursive", val2str(L, rule));
+ }
+ if (backtop >= MAXBACKVER)
+ return luaL_error(L, "too many pending calls/choices");
+ back[backtop].s = NULL;
+ back[backtop++].p = p + 1;
+ p = op + getposition(L, postable, p->i.offset);
+ continue;
+ }
+ case IBackCommit:
+ case ICommit: {
+ assert(backtop > 0 && p->i.offset > 0);
+ backtop--;
+ goto dojmp;
+ }
+ case IPartialCommit: {
+ assert(backtop > 0);
+ if (p->i.offset > 0) goto dojmp; /* forward jump */
+ else { /* loop will be detected when checking corresponding rule */
+ assert(postable != 0);
+ backtop--;
+ p++; /* just go on now */
+ continue;
+ }
+ }
+ case IBack: {
+ if (p->i.aux == 1 && isfixcheck(p + 1)) { /* char test? */
+ p++; /* skip back instruction */
+ p += sizei(p); /* skip char test */
+ }
+ else { /* standard lookbehind code */
+ assert((Opcode)(p - 1)->i.code == IChoice); /* look behind */
+ backtop--;
+ p += (p - 1)->i.offset;
+ assert((Opcode)(p - 1)->i.code == IFail); /* look behind */
+ }
+ continue;
+ }
+ case IAny:
+ case IChar:
+ case ISet: {
+ const Instruction *next = p + sizei(p);
+ if ((Opcode)next->i.code == IBack)
+ p = next + 1; /* continue after the back instruction */
+ else if (p->i.offset == 0) goto fail;
+ else /* jump */
+ p += p->i.offset;
+ continue;
+ }
+ case IJmp:
+ dojmp: {
+ p += p->i.offset;
+ continue;
+ }
+ case IFailTwice: /* 'not' predicate */
+ goto fail; /* body could have failed; try to backtrack it */
+ case IFail: {
+ if (p > op && (p - 1)->i.code == IBackCommit) { /* 'and' predicate? */
+ p++; /* pretend it succeeded and go ahead */
+ continue;
+ }
+ /* else failed: go through */
+ }
+ fail: { /* pattern failed: try to backtrack */
+ do {
+ if (backtop-- == 0)
+ return 1; /* no more backtracking */
+ } while (back[backtop].s == NULL);
+ p = back[backtop].p;
+ continue;
+ }
+ case ISpan:
+ case IOpenCapture: case ICloseCapture:
+ case IEmptyCapture: case IEmptyCaptureIdx:
+ case IFullCapture: {
+ p += sizei(p);
+ continue;
+ }
+ case ICloseRunTime: {
+ goto fail; /* be liberal in this case */
+ }
+ case IFunc: {
+ const char *r = (p+1)->f(dummy, dummy, dummy, (p+2)->buff);
+ if (r != NULL) { p += funcinstsize(p); }
+ else condfailed(p);
+ continue;
+ }
+ case IEnd: /* cannot happen (should stop before it) */
+ default: assert(0); return 0;
+ }
+ }
+ assert(backtop == 0);
+ return 0;
+}
+
+
+static void checkrule (lua_State *L, Instruction *op, int from, int to,
+ int postable, int rule) {
+ int i;
+ int lastopen = 0; /* more recent OpenCall seen in the code */
+ for (i = from; i < to; i += sizei(op + i)) {
+ if (op[i].i.code == IPartialCommit && op[i].i.offset < 0) { /* loop? */
+ int start = dest(op, i);
+ assert(op[start - 1].i.code == IChoice && dest(op, start - 1) == i + 1);
+ if (start <= lastopen) { /* loop does contain an open call? */
+ if (!verify(L, op, op + start, op + i, postable, rule)) /* check body */
+ luaL_error(L, "possible infinite loop in %s", val2str(L, rule));
+ }
+ }
+ else if (op[i].i.code == IOpenCall)
+ lastopen = i;
+ }
+ assert(op[i - 1].i.code == IRet);
+ verify(L, op, op + from, op + to - 1, postable, rule);
+}
+
+
+
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Building Patterns
+** =======================================================
+*/
+
+enum charsetanswer { NOINFO, ISCHARSET, VALIDSTARTS };
+
+typedef struct CharsetTag {
+ enum charsetanswer tag;
+ Charset cs;
+} CharsetTag;
+
+
+static Instruction *getpatt (lua_State *L, int idx, int *size);
+
+
+static void check2test (Instruction *p, int n) {
+ assert(ischeck(p) && n != 0);
+ p->i.offset = n;
+}
+
+
+/*
+** invert array slice p[0]-p[e] (both inclusive)
+*/
+static void invert (Instruction *p, int e) {
+ int i;
+ for (i = 0; i < e; i++, e--) {
+ Instruction temp = p[i];
+ p[i] = p[e];
+ p[e] = temp;
+ }
+}
+
+
+/*
+** rotate array slice p[0]-p[e] (both inclusive) 'n' steps
+** to the 'left'
+*/
+static void rotate (Instruction *p, int e, int n) {
+ invert(p, n - 1);
+ invert(p + n, e - n);
+ invert(p, e);
+}
+
+
+#define op_step(p) ((p)->i.code == IAny ? (p)->i.aux : 1)
+
+
+static int skipchecks (Instruction *p, int up, int *pn) {
+ int i, n = 0;
+ for (i = 0; isfixcheck(p + i); i += sizei(p + i)) {
+ int st = op_step(p + i);
+ if (n + st > MAXOFF - up) break;
+ n += st;
+ }
+ *pn = n;
+ return i;
+}
+
+
+#define ismovablecap(op) (ismovable(op) && getoff(op) < MAXOFF)
+
+static void optimizecaptures (Instruction *p) {
+ int i;
+ int limit = 0;
+ for (i = 0; p[i].i.code != IEnd; i += sizei(p + i)) {
+ if (isjmp(p + i) && dest(p, i) >= limit)
+ limit = dest(p, i) + 1; /* do not optimize jump targets */
+ else if (i >= limit && ismovablecap(p + i) && isfixcheck(p + i + 1)) {
+ int end, n, j; /* found a border capture|check */
+ int maxoff = getoff(p + i);
+ int start = i;
+ /* find first capture in the group */
+ while (start > limit && ismovablecap(p + start - 1)) {
+ start--;
+ if (getoff(p + start) > maxoff) maxoff = getoff(p + start);
+ }
+ end = skipchecks(p + i + 1, maxoff, &n) + i; /* find last check */
+ if (n == 0) continue; /* first check is too big to move across */
+ assert(n <= MAXOFF && start <= i && i < end);
+ for (j = start; j <= i; j++)
+ p[j].i.aux += (n << 4); /* correct offset of captures to be moved */
+ rotate(p + start, end - start, i - start + 1); /* move them up */
+ i = end;
+ assert(isfixcheck(p + start) && iscapture(p + i));
+ }
+ }
+}
+
+
+static int target (Instruction *p, int i) {
+ while (p[i].i.code == IJmp) i += p[i].i.offset;
+ return i;
+}
+
+
+static void optimizejumps (Instruction *p) {
+ int i;
+ for (i = 0; p[i].i.code != IEnd; i += sizei(p + i)) {
+ if (isjmp(p + i))
+ p[i].i.offset = target(p, dest(p, i)) - i;
+ }
+}
+
+
+static void optimizechoice (Instruction *p) {
+ assert(p->i.code == IChoice);
+ if (isfixcheck(p + 1)) {
+ int lc = sizei(p + 1);
+ rotate(p, lc, 1);
+ assert(isfixcheck(p) && (p + lc)->i.code == IChoice);
+ (p + lc)->i.aux = op_step(p);
+ check2test(p, (p + lc)->i.offset);
+ (p + lc)->i.offset -= lc;
+ }
+}
+
+
+/*
+** A 'headfail' pattern is a pattern that can only fails in its first
+** instruction, which must be a check.
+*/
+static int isheadfail (Instruction *p) {
+ if (!ischeck(p)) return 0;
+ /* check that other operations cannot fail */
+ for (p += sizei(p); p->i.code != IEnd; p += sizei(p))
+ if (!isnofail(p)) return 0;
+ return 1;
+}
+
+
+#define checkpattern(L, idx) ((Instruction *)luaL_checkudata(L, idx, PATTERN_T))
+
+
+/*
+** Return the number of elements in the ktable of a pattern.
+** in Lua 5.2, default "environment" for patterns is nil, not
+** a table. Treat it as an empty table.
+*/
+static int ktablelen (lua_State *L, int idx) {
+ if (!lua_istable(L, idx)) return 0;
+ else return lua_objlen(L, idx);
+}
+
+
+/*
+** join the elements of the ktable from pattern 'p1' into the ktable of
+** the pattern at the top of the stack ('p'). If 'p1' has no elements,
+** 'p' keeps its original ktable. If 'p' has no elements, it shares
+** 'p1' ktable. Otherwise, this function creates a new ktable for 'p'.
+** Return the offset of original 'p' elements in the new ktable.
+*/
+static int jointable (lua_State *L, int p1) {
+ int n, n1, i;
+ lua_getfenv(L, p1);
+ n1 = ktablelen(L, -1); /* number of elements in p1's env */
+ lua_getfenv(L, -2);
+ if (n1 == 0 || lua_equal(L, -2, -1)) {
+ lua_pop(L, 2);
+ return 0; /* no need to change anything */
+ }
+ n = ktablelen(L, -1); /* number of elements in p's env */
+ if (n == 0) {
+ lua_pop(L, 1); /* removes p env */
+ lua_setfenv(L, -2); /* p now shares p1's env */
+ return 0; /* no need to correct anything */
+ }
+ lua_createtable(L, n + n1, 0);
+ /* stack: p; p1 env; p env; new p env */
+ for (i = 1; i <= n; i++) {
+ lua_rawgeti(L, -2, i);
+ lua_rawseti(L, -2, i);
+ }
+ for (i = 1; i <= n1; i++) {
+ lua_rawgeti(L, -3, i);
+ lua_rawseti(L, -2, n + i);
+ }
+ lua_setfenv(L, -4); /* new table becomes p env */
+ lua_pop(L, 2); /* remove p1 env and old p env */
+ return n;
+}
+
+
+#define copypatt(p1,p2,sz) memcpy(p1, p2, (sz) * sizeof(Instruction));
+
+#define pattsize(L,idx) (lua_objlen(L, idx)/sizeof(Instruction) - 1)
+
+
+static int addpatt (lua_State *L, Instruction *p, int p1idx) {
+ Instruction *p1 = (Instruction *)lua_touserdata(L, p1idx);
+ int sz = pattsize(L, p1idx);
+ int corr = jointable(L, p1idx);
+ copypatt(p, p1, sz + 1);
+ if (corr != 0) {
+ Instruction *px;
+ for (px = p; px < p + sz; px += sizei(px)) {
+ if (isfenvoff(px) && px->i.offset != 0)
+ px->i.offset += corr;
+ }
+ }
+ return sz;
+}
+
+
+static void setinstaux (Instruction *i, Opcode op, int offset, int aux) {
+ assert(aux <= MAXAUX);
+ i->i.code = op;
+ i->i.offset = offset;
+ i->i.aux = aux;
+}
+
+#define setinst(i,op,off) setinstaux(i,op,off,0)
+
+#define setinstcap(i,op,idx,k,n) setinstaux(i,op,idx,((k) | ((n) << 4)))
+
+
+/*
+** create a new ktable for pattern at the stack top, mapping
+** '1' to the value at stack position 'vidx'.
+*/
+static int value2fenv (lua_State *L, int vidx) {
+ lua_createtable(L, 1, 0);
+ lua_pushvalue(L, vidx);
+ lua_rawseti(L, -2, 1);
+ lua_setfenv(L, -2);
+ return 1;
+}
+
+
+static Instruction *newpatt (lua_State *L, size_t n) {
+ Instruction *p;
+ if (n >= MAXPATTSIZE - 1)
+ luaL_error(L, "pattern too big");
+ p = (Instruction *)lua_newuserdata(L, (n + 1) * sizeof(Instruction));
+ luaL_getmetatable(L, PATTERN_T);
+ lua_setmetatable(L, -2);
+ setinst(p + n, IEnd, 0);
+ return p;
+}
+
+
+static void fillcharset (Instruction *p, Charset cs) {
+ switch (p[0].i.code) {
+ case ISet: {
+ loopset(i, cs[i] = p[1].buff[i]);
+ break;
+ }
+ case IChar: {
+ loopset(i, cs[i] = 0);
+ setchar(cs, p[0].i.aux);
+ break;
+ }
+ default: { /* any char may start unhandled instructions */
+ loopset(i, cs[i] = 0xff);
+ break;
+ }
+ }
+}
+
+
+/*
+** Function 'tocharset' gets information about which chars may be a
+** valid start for a pattern.
+*/
+
+static enum charsetanswer tocharset (Instruction *p, CharsetTag *c) {
+ if (isfixcheck(p)) {
+ fillcharset(p, c->cs);
+ if ((p + sizei(p))->i.code == IEnd && op_step(p) == 1)
+ c->tag = ISCHARSET;
+ else
+ c->tag = VALIDSTARTS;
+ }
+ else
+ c->tag = NOINFO;
+ return c->tag;
+}
+
+
+static int exclusiveset (Charset c1, Charset c2) {
+ /* non-empty intersection? */
+ loopset(i, {if ((c1[i] & c2[i]) != 0) return 0;});
+ return 1; /* no intersection */
+}
+
+
+static int exclusive (CharsetTag *c1, CharsetTag *c2) {
+ if (c1->tag == NOINFO || c2->tag == NOINFO)
+ return 0; /* one of them is not filled */
+ else return exclusiveset(c1->cs, c2->cs);
+}
+
+
+static Instruction *newcharset (lua_State *L) {
+ Instruction *p = newpatt(L, CHARSETINSTSIZE);
+ p[0].i.code = ISet;
+ p[0].i.offset = 0;
+ loopset(i, p[1].buff[i] = 0);
+ return p;
+}
+
+
+static int set_l (lua_State *L) {
+ size_t l;
+ const char *s = luaL_checklstring(L, 1, &l);
+ if (l == 1)
+ getpatt(L, 1, NULL); /* a unit set is equivalent to a literal */
+ else {
+ Instruction *p = newcharset(L);
+ while (l--) {
+ setchar(p[1].buff, (byte)(*s));
+ s++;
+ }
+ }
+ return 1;
+}
+
+
+static int range_l (lua_State *L) {
+ int arg;
+ int top = lua_gettop(L);
+ Instruction *p = newcharset(L);
+ for (arg = 1; arg <= top; arg++) {
+ int c;
+ size_t l;
+ const char *r = luaL_checklstring(L, arg, &l);
+ luaL_argcheck(L, l == 2, arg, "range must have two characters");
+ for (c = (byte)r[0]; c <= (byte)r[1]; c++)
+ setchar(p[1].buff, c);
+ }
+ return 1;
+}
+
+
+static int nter_l (lua_State *L) {
+ Instruction *p;
+ luaL_argcheck(L, !lua_isnoneornil(L, 1), 1, "non-nil value expected");
+ p = newpatt(L, 1);
+ setinst(p, IOpenCall, value2fenv(L, 1));
+ return 1;
+}
+
+
+
+static int testpattern (lua_State *L, int idx) {
+ if (lua_touserdata(L, idx)) { /* value is a userdata? */
+ if (lua_getmetatable(L, idx)) { /* does it have a metatable? */
+ luaL_getmetatable(L, PATTERN_T);
+ if (lua_rawequal(L, -1, -2)) { /* does it have the correct mt? */
+ lua_pop(L, 2); /* remove both metatables */
+ return 1;
+ }
+ }
+ }
+ return 0;
+}
+
+
+static Instruction *fix_l (lua_State *L, int t) {
+ Instruction *p;
+ int i;
+ int totalsize = 2; /* include initial call and jump */
+ int n = 0; /* number of rules */
+ int base = lua_gettop(L);
+ lua_newtable(L); /* to store relative positions of each rule */
+ lua_pushinteger(L, 1); /* default initial rule */
+ /* collect patterns and compute sizes */
+ lua_pushnil(L);
+ while (lua_next(L, t) != 0) {
+ int l;
+ if (lua_tonumber(L, -2) == 1 && lua_isstring(L, -1)) {
+ lua_replace(L, base + 2); /* use this value as initial rule */
+ continue;
+ }
+ if (!testpattern(L, -1))
+ luaL_error(L, "%s is not a pattern", val2str(L, -2));
+ l = pattsize(L, -1) + 1; /* space for pattern + ret */
+ if (totalsize >= MAXPATTSIZE - l)
+ luaL_error(L, "grammar too large");
+ luaL_checkstack(L, LUA_MINSTACK, "grammar has too many rules");
+ lua_insert(L, -2); /* put key on top */
+ lua_pushvalue(L, -1); /* duplicate key (for lua_next) */
+ lua_pushvalue(L, -1); /* duplicate key (to index positions table)) */
+ lua_pushinteger(L, totalsize); /* position for this rule */
+ lua_settable(L, base + 1); /* store key=>position in positions table */
+ totalsize += l;
+ n++;
+ }
+ luaL_argcheck(L, n > 0, t, "empty grammar");
+ p = newpatt(L, totalsize); /* create new pattern */
+ p++; /* save space for call */
+ setinst(p++, IJmp, totalsize - 1); /* after call, jumps to the end */
+ for (i = 1; i <= n; i++) { /* copy all rules into new pattern */
+ p += addpatt(L, p, base + 1 + i*2);
+ setinst(p++, IRet, 0);
+ }
+ p -= totalsize; /* back to first position */
+ totalsize = 2; /* go through each rule's position */
+ for (i = 1; i <= n; i++) { /* check all rules */
+ int l = pattsize(L, base + 1 + i*2) + 1;
+ checkrule(L, p, totalsize, totalsize + l, base + 1, base + 2 + i*2);
+ totalsize += l;
+ }
+ lua_pushvalue(L, base + 2); /* get initial rule */
+ lua_gettable(L, base + 1); /* get its position in postions table */
+ i = lua_tonumber(L, -1); /* convert to number */
+ lua_pop(L, 1);
+ if (i == 0) /* is it defined? */
+ luaL_error(L, "initial rule not defined in given grammar");
+ setinst(p, ICall, i); /* first instruction calls initial rule */
+ /* correct calls */
+ for (i = 0; i < totalsize; i += sizei(p + i)) {
+ if (p[i].i.code == IOpenCall) {
+ int pos = getposition(L, base + 1, p[i].i.offset);
+ p[i].i.code = (p[target(p, i + 1)].i.code == IRet) ? IJmp : ICall;
+ p[i].i.offset = pos - i;
+ }
+ }
+ optimizejumps(p);
+ lua_replace(L, t); /* put new pattern in old's position */
+ lua_settop(L, base); /* remove rules and positions table */
+ return p;
+}
+
+
+static Instruction *any (lua_State *L, int n, int extra, int *offsetp) {
+ int offset = offsetp ? *offsetp : 0;
+ Instruction *p = newpatt(L, (n - 1)/UCHAR_MAX + extra + 1);
+ Instruction *p1 = p + offset;
+ for (; n > UCHAR_MAX; n -= UCHAR_MAX)
+ setinstaux(p1++, IAny, 0, UCHAR_MAX);
+ setinstaux(p1++, IAny, 0, n);
+ if (offsetp) *offsetp = p1 - p;
+ return p;
+}
+
+
+static Instruction *getpatt (lua_State *L, int idx, int *size) {
+ Instruction *p;
+ switch (lua_type(L, idx)) {
+ case LUA_TSTRING: {
+ size_t i, len;
+ const char *s = lua_tolstring(L, idx, &len);
+ p = newpatt(L, len);
+ for (i = 0; i < len; i++)
+ setinstaux(p + i, IChar, 0, (byte)s[i]);
+ lua_replace(L, idx);
+ break;
+ }
+ case LUA_TNUMBER: {
+ int n = lua_tointeger(L, idx);
+ if (n == 0) /* empty pattern? */
+ p = newpatt(L, 0);
+ else if (n > 0)
+ p = any(L, n, 0, NULL);
+ else if (-n <= UCHAR_MAX) {
+ p = newpatt(L, 2);
+ setinstaux(p, IAny, 2, -n);
+ setinst(p + 1, IFail, 0);
+ }
+ else {
+ int offset = 2; /* space for ITestAny & IChoice */
+ p = any(L, -n - UCHAR_MAX, 3, &offset);
+ setinstaux(p, IAny, offset + 1, UCHAR_MAX);
+ setinstaux(p + 1, IChoice, offset, UCHAR_MAX);
+ setinst(p + offset, IFailTwice, 0);
+ }
+ lua_replace(L, idx);
+ break;
+ }
+ case LUA_TBOOLEAN: {
+ if (lua_toboolean(L, idx)) /* true? */
+ p = newpatt(L, 0); /* empty pattern (always succeeds) */
+ else {
+ p = newpatt(L, 1);
+ setinst(p, IFail, 0);
+ }
+ lua_replace(L, idx);
+ break;
+ }
+ case LUA_TTABLE: {
+ p = fix_l(L, idx);
+ break;
+ }
+ case LUA_TFUNCTION: {
+ p = newpatt(L, 2);
+ setinstcap(p, IOpenCapture, value2fenv(L, idx), Cruntime, 0);
+ setinstcap(p + 1, ICloseRunTime, 0, Cclose, 0);
+ lua_replace(L, idx);
+ break;
+ }
+ default: {
+ p = checkpattern(L, idx);
+ break;
+ }
+ }
+ if (size) *size = pattsize(L, idx);
+ return p;
+}
+
+
+static int getpattl (lua_State *L, int idx) {
+ int size;
+ getpatt(L, idx, &size);
+ return size;
+}
+
+
+static int pattern_l (lua_State *L) {
+ lua_settop(L, 1);
+ getpatt(L, 1, NULL);
+ return 1;
+}
+
+
+#define isany(p) ((p)->i.code == IAny && ((p) + 1)->i.code == IEnd)
+#define isfail(p) ((p)->i.code == IFail)
+#define issucc(p) ((p)->i.code == IEnd)
+
+static int concat_l (lua_State *L) {
+ /* p1; p2; */
+ int l1, l2;
+ Instruction *p1 = getpatt(L, 1, &l1);
+ Instruction *p2 = getpatt(L, 2, &l2);
+ if (isfail(p1) || issucc(p2))
+ lua_pushvalue(L, 1); /* fail * x == fail; x * true == x */
+ else if (isfail(p2) || issucc(p1))
+ lua_pushvalue(L, 2); /* x * fail == fail; true * x == x */
+ else if (isany(p1) && isany(p2))
+ any(L, p1->i.aux + p2->i.aux, 0, NULL);
+ else {
+ Instruction *op = newpatt(L, l1 + l2);
+ Instruction *p = op + addpatt(L, op, 1);
+ addpatt(L, p, 2);
+ optimizecaptures(op);
+ }
+ return 1;
+}
+
+
+static int diff_l (lua_State *L) {
+ int l1, l2;
+ Instruction *p1 = getpatt(L, 1, &l1);
+ Instruction *p2 = getpatt(L, 2, &l2);
+ CharsetTag st1, st2;
+ if (tocharset(p1, &st1) == ISCHARSET && tocharset(p2, &st2) == ISCHARSET) {
+ Instruction *p = newcharset(L);
+ loopset(i, p[1].buff[i] = st1.cs[i] & ~st2.cs[i]);
+ }
+ else if (isheadfail(p2)) {
+ Instruction *p = newpatt(L, l2 + 1 + l1);
+ p += addpatt(L, p, 2);
+ check2test(p - l2, l2 + 1);
+ setinst(p++, IFail, 0);
+ addpatt(L, p, 1);
+ }
+ else { /* !e2 . e1 */
+ /* !e -> choice L1; e; failtwice; L1: ... */
+ Instruction *p = newpatt(L, 1 + l2 + 1 + l1);
+ Instruction *pi = p;
+ setinst(p++, IChoice, 1 + l2 + 1);
+ p += addpatt(L, p, 2);
+ setinst(p++, IFailTwice, 0);
+ addpatt(L, p, 1);
+ optimizechoice(pi);
+ }
+ return 1;
+}
+
+
+static int unm_l (lua_State *L) {
+ Instruction *p = getpatt(L, 1, NULL);
+ if (isfail(p)) { /* -false? */
+ newpatt(L, 0); /* true */
+ return 1;
+ }
+ else if (issucc(p)) { /* -true? */
+ Instruction *p1 = newpatt(L, 1); /* false */
+ setinst(p1, IFail, 0);
+ return 1;
+ }
+ else { /* -A == '' - A */
+ lua_pushliteral(L, "");
+ lua_insert(L, 1);
+ return diff_l(L);
+ }
+}
+
+
+static int pattand_l (lua_State *L) {
+ int l1;
+ CharsetTag st1;
+ Instruction *p1 = getpatt(L, 1, &l1);
+ if (isfail(p1) || issucc(p1))
+ lua_pushvalue(L, 1); /* &fail == fail; &true == true */
+ else if (tocharset(p1, &st1) == ISCHARSET) {
+ Instruction *p = newpatt(L, l1 + 1);
+ copypatt(p, p1, l1); p += l1;
+ setinstaux(p, IBack, 0, 1);
+ }
+ else { /* Choice L1; p1; BackCommit L2; L1: Fail; L2: */
+ Instruction *p = newpatt(L, 1 + l1 + 2);
+ setinst(p++, IChoice, 1 + l1 + 1);
+ p += addpatt(L, p, 1);
+ setinst(p++, IBackCommit, 2);
+ setinst(p, IFail, 0);
+ }
+ return 1;
+}
+
+
+static int nocalls (const Instruction *p) {
+ for (; (Opcode)p->i.code != IEnd; p += sizei(p))
+ if ((Opcode)p->i.code == IOpenCall) return 0;
+ return 1;
+}
+
+
+static int pattbehind (lua_State *L) {
+ int l1;
+ CharsetTag st1;
+ Instruction *p1 = getpatt(L, 1, &l1);
+ int n = luaL_optint(L, 2, 1);
+ luaL_argcheck(L, n <= MAXAUX, 2, "lookbehind delta too large");
+ if (!nocalls(p1))
+ luaL_error(L, "lookbehind pattern cannot contain non terminals");
+ if (isfail(p1) || issucc(p1))
+ lua_pushvalue(L, 1); /* tag == NOINFO) return 1;
+ assert(p1->i.offset != 0);
+ switch (p1->i.code) {
+ case IChar: return testchar(st2->cs, p1->i.aux);
+ case ISet: return !exclusiveset(st2->cs, (p1 + 1)->buff);
+ default: assert(p1->i.code == IAny); return 1;
+ }
+}
+
+
+static Instruction *basicUnion (lua_State *L, Instruction *p1, int l1,
+ int l2, int *size, CharsetTag *st2) {
+ Instruction *op;
+ CharsetTag st1;
+ tocharset(p1, &st1);
+ if (st1.tag == ISCHARSET && st2->tag == ISCHARSET) {
+ Instruction *p = auxnew(L, &op, size, CHARSETINSTSIZE);
+ setinst(p, ISet, 0);
+ loopset(i, p[1].buff[i] = st1.cs[i] | st2->cs[i]);
+ }
+ else if (exclusive(&st1, st2) || isheadfail(p1)) {
+ Instruction *p = auxnew(L, &op, size, l1 + 1 + l2);
+ copypatt(p, p1, l1);
+ check2test(p, l1 + 1);
+ p += l1;
+ setinst(p++, IJmp, l2 + 1);
+ addpatt(L, p, 2);
+ }
+ else {
+ /* choice L1; e1; commit L2; L1: e2; L2: ... */
+ Instruction *p = auxnew(L, &op, size, 1 + l1 + 1 + l2);
+ setinst(p++, IChoice, 1 + l1 + 1);
+ copypatt(p, p1, l1); p += l1;
+ setinst(p++, ICommit, 1 + l2);
+ addpatt(L, p, 2);
+ optimizechoice(p - (1 + l1 + 1));
+ }
+ return op;
+}
+
+
+static Instruction *separateparts (lua_State *L, Instruction *p1, int l1,
+ int l2, int *size, CharsetTag *st2) {
+ int sp = firstpart(p1, l1);
+ if (sp == 0) /* first part is entire p1? */
+ return basicUnion(L, p1, l1, l2, size, st2);
+ else if ((p1 + sp - 1)->i.code == ICommit || !interfere(p1, sp, st2)) {
+ Instruction *p;
+ int init = *size;
+ int end = init + sp;
+ *size = end;
+ p = separateparts(L, p1 + sp, l1 - sp, l2, size, st2);
+ copypatt(p + init, p1, sp);
+ (p + end - 1)->i.offset = *size - (end - 1);
+ return p;
+ }
+ else { /* must change back to non-optimized choice */
+ Instruction *p;
+ int init = *size;
+ int end = init + sp + 1; /* needs one extra instruction (choice) */
+ int sizefirst = sizei(p1); /* size of p1's first instruction (the test) */
+ *size = end;
+ p = separateparts(L, p1 + sp, l1 - sp, l2, size, st2);
+ copypatt(p + init, p1, sizefirst); /* copy the test */
+ (p + init)->i.offset++; /* correct jump (because of new instruction) */
+ init += sizefirst;
+ setinstaux(p + init, IChoice, sp - sizefirst + 1, 1); init++;
+ copypatt(p + init, p1 + sizefirst, sp - sizefirst - 1);
+ init += sp - sizefirst - 1;
+ setinst(p + init, ICommit, *size - (end - 1));
+ return p;
+ }
+}
+
+
+static int union_l (lua_State *L) {
+ int l1, l2;
+ int size = 0;
+ Instruction *p1 = getpatt(L, 1, &l1);
+ Instruction *p2 = getpatt(L, 2, &l2);
+ CharsetTag st2;
+ if (isfail(p1)) /* check for simple identities */
+ lua_pushvalue(L, 2); /* fail / a == a */
+ else if (isfail(p2) || issucc(p1))
+ lua_pushvalue(L, 1); /* a / fail == a; true / a == true */
+ else {
+ tocharset(p2, &st2);
+ separateparts(L, p1, l1, l2, &size, &st2);
+ }
+ return 1;
+}
+
+
+static int repeatcharset (lua_State *L, Charset cs, int l1, int n) {
+ /* e; ...; e; span; */
+ int i;
+ Instruction *p = newpatt(L, n*l1 + CHARSETINSTSIZE);
+ for (i = 0; i < n; i++) {
+ p += addpatt(L, p, 1);
+ }
+ setinst(p, ISpan, 0);
+ loopset(k, p[1].buff[k] = cs[k]);
+ return 1;
+}
+
+
+static Instruction *repeatheadfail (lua_State *L, int l1, int n) {
+ /* e; ...; e; L2: e'(L1); jump L2; L1: ... */
+ int i;
+ Instruction *p = newpatt(L, (n + 1)*l1 + 1);
+ Instruction *op = p;
+ for (i = 0; i < n; i++) {
+ p += addpatt(L, p, 1);
+ }
+ p += addpatt(L, p, 1);
+ check2test(p - l1, l1 + 1);
+ setinst(p, IJmp, -l1);
+ return op;
+}
+
+
+static Instruction *repeats (lua_State *L, Instruction *p1, int l1, int n) {
+ /* e; ...; e; choice L1; L2: e; partialcommit L2; L1: ... */
+ int i;
+ Instruction *op = newpatt(L, (n + 1)*l1 + 2);
+ Instruction *p = op;
+ if (!verify(L, p1, p1, p1 + l1, 0, 0))
+ luaL_error(L, "loop body may accept empty string");
+ for (i = 0; i < n; i++) {
+ p += addpatt(L, p, 1);
+ }
+ setinst(p++, IChoice, 1 + l1 + 1);
+ p += addpatt(L, p, 1);
+ setinst(p, IPartialCommit, -l1);
+ return op;
+}
+
+
+static void optionalheadfail (lua_State *L, int l1, int n) {
+ Instruction *op = newpatt(L, n * l1);
+ Instruction *p = op;
+ int i;
+ for (i = 0; i < n; i++) {
+ p += addpatt(L, p, 1);
+ check2test(p - l1, (n - i)*l1);
+ }
+}
+
+
+static void optionals (lua_State *L, int l1, int n) {
+ /* choice L1; e; partialcommit L2; L2: ... e; L1: commit L3; L3: ... */
+ int i;
+ Instruction *op = newpatt(L, n*(l1 + 1) + 1);
+ Instruction *p = op;
+ setinst(p++, IChoice, 1 + n*(l1 + 1));
+ for (i = 0; i < n; i++) {
+ p += addpatt(L, p, 1);
+ setinst(p++, IPartialCommit, 1);
+ }
+ setinst(p - 1, ICommit, 1); /* correct last commit */
+ optimizechoice(op);
+}
+
+
+static int star_l (lua_State *L) {
+ int l1;
+ int n = luaL_checkint(L, 2);
+ Instruction *p1 = getpatt(L, 1, &l1);
+ if (n >= 0) {
+ CharsetTag st;
+ Instruction *op;
+ if (tocharset(p1, &st) == ISCHARSET)
+ return repeatcharset(L, st.cs, l1, n);
+ if (isheadfail(p1))
+ op = repeatheadfail(L, l1, n);
+ else
+ op = repeats(L, p1, l1, n);
+ optimizecaptures(op);
+ optimizejumps(op);
+ }
+ else {
+ if (isheadfail(p1))
+ optionalheadfail(L, l1, -n);
+ else
+ optionals(L, l1, -n);
+ }
+ return 1;
+}
+
+
+static int getlabel (lua_State *L, int labelidx) {
+ if (labelidx == 0) return 0;
+ else return value2fenv(L, labelidx);
+}
+
+
+static int capture_aux (lua_State *L, int kind, int labelidx) {
+ int l1, n;
+ Instruction *p1 = getpatt(L, 1, &l1);
+ int lc = skipchecks(p1, 0, &n);
+ if (lc == l1) { /* got whole pattern? */
+ /* may use a IFullCapture instruction at its end */
+ Instruction *p = newpatt(L, l1 + 1);
+ int label = getlabel(L, labelidx);
+ p += addpatt(L, p, 1);
+ setinstcap(p, IFullCapture, label, kind, n);
+ }
+ else { /* must use open-close pair */
+ Instruction *op = newpatt(L, 1 + l1 + 1);
+ Instruction *p = op;
+ setinstcap(p++, IOpenCapture, getlabel(L, labelidx), kind, 0);
+ p += addpatt(L, p, 1);
+ setinstcap(p, ICloseCapture, 0, Cclose, 0);
+ optimizecaptures(op);
+ }
+ return 1;
+}
+
+
+static int capture_l (lua_State *L) { return capture_aux(L, Csimple, 0); }
+static int tcapture_l (lua_State *L) { return capture_aux(L, Ctable, 0); }
+static int capsubst_l (lua_State *L) { return capture_aux(L, Csubst, 0); }
+
+static int rcapture_l (lua_State *L) {
+ switch (lua_type(L, 2)) {
+ case LUA_TFUNCTION: return capture_aux(L, Cfunction, 2);
+ case LUA_TTABLE: return capture_aux(L, Cquery, 2);
+ case LUA_TSTRING: return capture_aux(L, Cstring, 2);
+ default: return luaL_argerror(L, 2, "invalid replacement value");
+ }
+}
+
+
+static int fold_l (lua_State *L) {
+ luaL_checktype(L, 2, LUA_TFUNCTION);
+ return capture_aux(L, Cfold, 2);
+}
+
+
+static int group_l (lua_State *L) {
+ if (lua_isnoneornil(L, 2))
+ return capture_aux(L, Cgroup, 0);
+ else {
+ luaL_checkstring(L, 2);
+ return capture_aux(L, Cgroup, 2);
+ }
+}
+
+
+static int position_l (lua_State *L) {
+ Instruction *p = newpatt(L, 1);
+ setinstcap(p, IEmptyCapture, 0, Cposition, 0);
+ return 1;
+}
+
+
+static int backref_l (lua_State *L) {
+ Instruction *p = newpatt(L, 1);
+ int n = getlabel(L, 1);
+ setinstcap(p, IEmptyCaptureIdx, n, Cbackref, 0);
+ return 1;
+}
+
+
+static int argcap_l (lua_State *L) {
+ int n = luaL_checkint(L, 1);
+ Instruction *p = newpatt(L, 1);
+ luaL_argcheck(L, 0 < n && n <= SHRT_MAX, 1, "invalid argument index");
+ setinstcap(p, IEmptyCapture, n, Carg, 0);
+ return 1;
+}
+
+
+static int matchtime_l (lua_State *L) {
+ int l1 = getpattl(L, 1);
+ Instruction *op = newpatt(L, 1 + l1 + 1);
+ Instruction *p = op;
+ luaL_checktype(L, 2, LUA_TFUNCTION);
+ setinstcap(p++, IOpenCapture, value2fenv(L, 2), Cruntime, 0);
+ p += addpatt(L, p, 1);
+ setinstcap(p, ICloseRunTime, 0, Cclose, 0);
+ optimizecaptures(op);
+ return 1;
+}
+
+
+static int capconst_l (lua_State *L) {
+ int i, j;
+ int n = lua_gettop(L);
+ Instruction *p = newpatt(L, n > 1 ? n + 2 : n);
+ lua_createtable(L, n, 0); /* new environment for the new pattern */
+ if (n > 1) setinstcap(p++, IOpenCapture, 0, Cgroup, 0);
+ for (i = j = 1; i <= n; i++) {
+ if (lua_isnil(L, i))
+ setinstcap(p++, IEmptyCaptureIdx, 0, Cconst, 0);
+ else {
+ setinstcap(p++, IEmptyCaptureIdx, j, Cconst, 0);
+ lua_pushvalue(L, i);
+ lua_rawseti(L, -2, j++);
+ }
+ }
+ if (n > 1) setinstcap(p++, ICloseCapture, 0, Cclose, 0);
+ lua_setfenv(L, -2); /* set environment */
+ return 1;
+}
+
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** User-Defined Patterns
+** =======================================================
+*/
+
+static void l_newpf (lua_State *L, PattFunc f, const void *ud, size_t l) {
+ int n = instsize(l) + 1;
+ Instruction *p = newpatt(L, n);
+ if (n > MAXAUX) luaL_error(L, "pattern data too long");
+ p[0].i.code = IFunc;
+ p[0].i.aux = n - 2;
+ p[0].i.offset = 0;
+ p[1].f = f;
+ memcpy(p[2].buff, ud, l);
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** Captures
+** =======================================================
+*/
+
+
+typedef struct CapState {
+ Capture *cap; /* current capture */
+ Capture *ocap; /* (original) capture list */
+ lua_State *L;
+ int ptop; /* index of last argument to 'match' */
+ const char *s; /* original string */
+ int valuecached; /* value stored in cache slot */
+} CapState;
+
+
+#define captype(cap) ((cap)->kind)
+
+#define isclosecap(cap) (captype(cap) == Cclose)
+
+#define closeaddr(c) ((c)->s + (c)->siz - 1)
+
+#define isfullcap(cap) ((cap)->siz != 0)
+
+#define getfromenv(cs,v) lua_rawgeti((cs)->L, penvidx((cs)->ptop), v)
+#define pushluaval(cs) getfromenv(cs, (cs)->cap->idx)
+
+#define pushsubject(cs, c) lua_pushlstring((cs)->L, (c)->s, (c)->siz - 1)
+
+
+#define updatecache(cs,v) { if ((v) != (cs)->valuecached) updatecache_(cs,v); }
+
+
+static void updatecache_ (CapState *cs, int v) {
+ getfromenv(cs, v);
+ lua_replace(cs->L, subscache(cs));
+ cs->valuecached = v;
+}
+
+
+static int pushcapture (CapState *cs);
+
+
+static Capture *findopen (Capture *cap) {
+ int n = 0;
+ for (;;) {
+ cap--;
+ if (isclosecap(cap)) n++;
+ else if (!isfullcap(cap))
+ if (n-- == 0) return cap;
+ }
+}
+
+
+static Capture *nextcap (Capture *cap) {
+ if (isfullcap(cap)) return cap + 1;
+ else {
+ int n = 0;
+ for (;;) {
+ cap++;
+ if (isclosecap(cap)) {
+ if (n-- == 0) return cap + 1;
+ }
+ else if (!isfullcap(cap)) n++;
+ }
+ }
+}
+
+
+static int pushallvalues (CapState *cs, int addextra) {
+ Capture *co = cs->cap;
+ int n = 0;
+ if (isfullcap(cs->cap++)) {
+ pushsubject(cs, co); /* push whole match */
+ return 1;
+ }
+ while (!isclosecap(cs->cap))
+ n += pushcapture(cs);
+ if (addextra || n == 0) { /* need extra? */
+ lua_pushlstring(cs->L, co->s, cs->cap->s - co->s); /* push whole match */
+ n++;
+ }
+ cs->cap++; /* skip close entry */
+ return n;
+}
+
+
+static Capture *findback (CapState *cs, Capture *cap) {
+ lua_State *L = cs->L;
+ for (;;) {
+ if (cap == cs->ocap) { /* not found */
+ const char *s = lua_tostring(L, -1);
+ if (s == NULL) s = lua_pushfstring(L, "(a %s)", luaL_typename(L, -1));
+ luaL_error(L, "back reference '%s' not found", s);
+ }
+ cap--;
+ if (isclosecap(cap))
+ cap = findopen(cap);
+ else if (!isfullcap(cap))
+ continue; /* opening an enclosing capture: skip and get previous */
+ if (captype(cap) == Cgroup) {
+ getfromenv(cs, cap->idx); /* get group name */
+ if (lua_equal(L, -2, -1)) { /* right group? */
+ lua_pop(L, 2); /* remove reference name and group name */
+ return cap;
+ }
+ else lua_pop(L, 1); /* remove group name */
+ }
+ }
+}
+
+
+static int backrefcap (CapState *cs) {
+ int n;
+ Capture *curr = cs->cap;
+ pushluaval(cs); /* reference name */
+ cs->cap = findback(cs, curr);
+ n = pushallvalues(cs, 0);
+ cs->cap = curr + 1;
+ return n;
+}
+
+
+static int tablecap (CapState *cs) {
+ lua_State *L = cs->L;
+ int n = 0;
+ lua_newtable(L);
+ if (isfullcap(cs->cap++))
+ return 1; /* table is empty */
+ while (!isclosecap(cs->cap)) {
+ if (captype(cs->cap) == Cgroup && cs->cap->idx != 0) { /* named group? */
+ int k;
+ pushluaval(cs); /* push group name */
+ k = pushallvalues(cs, 0);
+ if (k == 0) { /* no value? */
+ lua_pop(L, 1); /* remove group name */
+ continue; /* and go on */
+ }
+ else if (k > 1)
+ lua_pop(L, k - 1); /* keep just one value */
+ lua_settable(L, -3);
+ }
+ else {
+ int i;
+ int k = pushcapture(cs);
+ for (i = k; i > 0; i--)
+ lua_rawseti(L, -(i + 1), n + i);
+ n += k;
+ }
+ }
+ cs->cap++; /* skip close entry */
+ return 1;
+}
+
+
+static int querycap (CapState *cs) {
+ int idx = cs->cap->idx;
+ int n = pushallvalues(cs, 0);
+ if (n > 1) /* extra captures? */
+ lua_pop(cs->L, n - 1); /* throw them away */
+ updatecache(cs, idx);
+ lua_gettable(cs->L, subscache(cs));
+ if (!lua_isnil(cs->L, -1))
+ return 1;
+ else {
+ lua_pop(cs->L, 1); /* remove value */
+ return 0;
+ }
+}
+
+
+static int foldcap (CapState *cs) {
+ int n;
+ lua_State *L = cs->L;
+ int idx = cs->cap->idx;
+ if (isfullcap(cs->cap++) || isclosecap(cs->cap) || (n = pushcapture(cs)) == 0)
+ return luaL_error(L, "no initial value for fold capture");
+ if (n > 1)
+ lua_pop(L, n - 1); /* leave only one result */
+ while (!isclosecap(cs->cap)) {
+ updatecache(cs, idx);
+ lua_pushvalue(L, subscache(cs)); /* get folding function */
+ lua_insert(L, -2); /* put it before accumulator */
+ n = pushcapture(cs); /* get other captures */
+ lua_call(L, n + 1, 1); /* call folding function */
+ }
+ cs->cap++; /* skip close entry */
+ return 1;
+}
+
+
+static int functioncap (CapState *cs) {
+ int n;
+ int top = lua_gettop(cs->L);
+ pushluaval(cs);
+ n = pushallvalues(cs, 0);
+ lua_call(cs->L, n, LUA_MULTRET);
+ return lua_gettop(cs->L) - top;
+}
+
+
+static int runtimecap (lua_State *L, Capture *close, Capture *ocap,
+ const char *o, const char *s, int ptop) {
+ CapState cs;
+ int n;
+ Capture *open = findopen(close);
+ assert(captype(open) == Cruntime);
+ close->kind = Cclose;
+ close->s = s;
+ cs.ocap = ocap; cs.cap = open; cs.L = L;
+ cs.s = o; cs.valuecached = 0; cs.ptop = ptop;
+ luaL_checkstack(L, 4, "too many runtime captures");
+ pushluaval(&cs);
+ lua_pushvalue(L, SUBJIDX); /* push original subject */
+ lua_pushinteger(L, s - o + 1); /* current position */
+ n = pushallvalues(&cs, 0);
+ lua_call(L, n + 2, LUA_MULTRET);
+ return close - open;
+}
+
+
+
+typedef struct StrAux {
+ int isstring;
+ union {
+ Capture *cp;
+ struct {
+ const char *s;
+ const char *e;
+ } s;
+ } u;
+} StrAux;
+
+#define MAXSTRCAPS 10
+
+static int getstrcaps (CapState *cs, StrAux *cps, int n) {
+ int k = n++;
+ cps[k].isstring = 1;
+ cps[k].u.s.s = cs->cap->s;
+ if (!isfullcap(cs->cap++)) {
+ while (!isclosecap(cs->cap)) {
+ if (n >= MAXSTRCAPS) /* too many captures? */
+ cs->cap = nextcap(cs->cap); /* skip it */
+ else if (captype(cs->cap) == Csimple)
+ n = getstrcaps(cs, cps, n);
+ else {
+ cps[n].isstring = 0;
+ cps[n].u.cp = cs->cap;
+ cs->cap = nextcap(cs->cap);
+ n++;
+ }
+ }
+ cs->cap++; /* skip close */
+ }
+ cps[k].u.s.e = closeaddr(cs->cap - 1);
+ return n;
+}
+
+
+/*
+** add next capture (which should be a string) to buffer
+*/
+static int addonestring (luaL_Buffer *b, CapState *cs, const char *what);
+
+
+static void stringcap (luaL_Buffer *b, CapState *cs) {
+ StrAux cps[MAXSTRCAPS];
+ int n;
+ size_t len, i;
+ const char *c;
+ updatecache(cs, cs->cap->idx);
+ c = lua_tolstring(cs->L, subscache(cs), &len);
+ n = getstrcaps(cs, cps, 0) - 1;
+ for (i = 0; i < len; i++) {
+ if (c[i] != '%' || c[++i] < '0' || c[i] > '9')
+ luaL_addchar(b, c[i]);
+ else {
+ int l = c[i] - '0';
+ if (l > n)
+ luaL_error(cs->L, "invalid capture index (%d)", l);
+ else if (cps[l].isstring)
+ luaL_addlstring(b, cps[l].u.s.s, cps[l].u.s.e - cps[l].u.s.s);
+ else {
+ Capture *curr = cs->cap;
+ cs->cap = cps[l].u.cp;
+ if (addonestring(b, cs, "capture") == 0)
+ luaL_error(cs->L, "no values in capture index %d", l);
+ cs->cap = curr;
+ }
+ }
+ }
+}
+
+
+static void substcap (luaL_Buffer *b, CapState *cs) {
+ const char *curr = cs->cap->s;
+ if (isfullcap(cs->cap)) /* no nested captures? */
+ luaL_addlstring(b, curr, cs->cap->siz - 1); /* keep original text */
+ else {
+ cs->cap++;
+ while (!isclosecap(cs->cap)) {
+ const char *next = cs->cap->s;
+ luaL_addlstring(b, curr, next - curr); /* add text up to capture */
+ if (addonestring(b, cs, "replacement") == 0) /* no capture value? */
+ curr = next; /* keep original text in final result */
+ else
+ curr = closeaddr(cs->cap - 1); /* continue after match */
+ }
+ luaL_addlstring(b, curr, cs->cap->s - curr); /* add last piece of text */
+ }
+ cs->cap++; /* go to next capture */
+}
+
+
+static int addonestring (luaL_Buffer *b, CapState *cs, const char *what) {
+ switch (captype(cs->cap)) {
+ case Cstring:
+ stringcap(b, cs); /* add capture directly to buffer */
+ return 1;
+ case Csubst:
+ substcap(b, cs); /* add capture directly to buffer */
+ return 1;
+ default: {
+ lua_State *L = cs->L;
+ int n = pushcapture(cs);
+ if (n > 0) {
+ if (n > 1) lua_pop(L, n - 1); /* only one result */
+ if (!lua_isstring(L, -1))
+ luaL_error(L, "invalid %s value (a %s)", what, luaL_typename(L, -1));
+ luaL_addvalue(b);
+ }
+ return n;
+ }
+ }
+}
+
+
+static int pushcapture (CapState *cs) {
+ luaL_checkstack(cs->L, 4, "too many captures");
+ switch (captype(cs->cap)) {
+ case Cposition: {
+ lua_pushinteger(cs->L, cs->cap->s - cs->s + 1);
+ cs->cap++;
+ return 1;
+ }
+ case Cconst: {
+ pushluaval(cs);
+ cs->cap++;
+ return 1;
+ }
+ case Carg: {
+ int arg = (cs->cap++)->idx;
+ if (arg + FIXEDARGS > cs->ptop)
+ return luaL_error(cs->L, "reference to absent argument #%d", arg);
+ lua_pushvalue(cs->L, arg + FIXEDARGS);
+ return 1;
+ }
+ case Csimple: {
+ int k = pushallvalues(cs, 1);
+ if (k > 1)
+ lua_insert(cs->L, -k); /* whole match is first result */
+ return k;
+ }
+ case Cruntime: {
+ int n = 0;
+ while (!isclosecap(cs->cap++)) {
+ luaL_checkstack(cs->L, 4, "too many captures");
+ lua_pushvalue(cs->L, (cs->cap - 1)->idx);
+ n++;
+ }
+ return n;
+ }
+ case Cstring: {
+ luaL_Buffer b;
+ luaL_buffinit(cs->L, &b);
+ stringcap(&b, cs);
+ luaL_pushresult(&b);
+ return 1;
+ }
+ case Csubst: {
+ luaL_Buffer b;
+ luaL_buffinit(cs->L, &b);
+ substcap(&b, cs);
+ luaL_pushresult(&b);
+ return 1;
+ }
+ case Cgroup: {
+ if (cs->cap->idx == 0) /* anonymous group? */
+ return pushallvalues(cs, 0); /* add all nested values */
+ else { /* named group: add no values */
+ cs->cap = nextcap(cs->cap); /* skip capture */
+ return 0;
+ }
+ }
+ case Cbackref: return backrefcap(cs);
+ case Ctable: return tablecap(cs);
+ case Cfunction: return functioncap(cs);
+ case Cquery: return querycap(cs);
+ case Cfold: return foldcap(cs);
+ default: assert(0); return 0;
+ }
+}
+
+
+static int getcaptures (lua_State *L, const char *s, const char *r, int ptop) {
+ Capture *capture = (Capture *)lua_touserdata(L, caplistidx(ptop));
+ int n = 0;
+ if (!isclosecap(capture)) { /* is there any capture? */
+ CapState cs;
+ cs.ocap = cs.cap = capture; cs.L = L;
+ cs.s = s; cs.valuecached = 0; cs.ptop = ptop;
+ do { /* collect their values */
+ n += pushcapture(&cs);
+ } while (!isclosecap(cs.cap));
+ }
+ if (n == 0) { /* no capture values? */
+ lua_pushinteger(L, r - s + 1); /* return only end position */
+ n = 1;
+ }
+ return n;
+}
+
+/* }====================================================== */
+
+
+static int version_l (lua_State *L) {
+ lua_pushstring(L, VERSION);
+ return 1;
+}
+
+
+static int type_l (lua_State *L) {
+ if (testpattern(L, 1))
+ lua_pushliteral(L, "pattern");
+ else
+ lua_pushnil(L);
+ return 1;
+}
+
+
+static void createcat (lua_State *L, const char *catname, int (catf) (int)) {
+ Instruction *p = newcharset(L);
+ int i;
+ for (i = 0; i < CHAR_MAX; i++)
+ if (catf(i)) setchar(p[1].buff, i);
+ lua_setfield(L, -2, catname);
+}
+
+
+static int locale_l (lua_State *L) {
+ if (lua_isnoneornil(L, 1)) {
+ lua_settop(L, 0);
+ lua_createtable(L, 0, 12);
+ }
+ else {
+ luaL_checktype(L, 1, LUA_TTABLE);
+ lua_settop(L, 1);
+ }
+ createcat(L, "alnum", isalnum);
+ createcat(L, "alpha", isalpha);
+ createcat(L, "cntrl", iscntrl);
+ createcat(L, "digit", isdigit);
+ createcat(L, "graph", isgraph);
+ createcat(L, "lower", islower);
+ createcat(L, "print", isprint);
+ createcat(L, "punct", ispunct);
+ createcat(L, "space", isspace);
+ createcat(L, "upper", isupper);
+ createcat(L, "xdigit", isxdigit);
+ return 1;
+}
+
+
+static int setmax (lua_State *L) {
+ luaL_optinteger(L, 1, -1);
+ lua_settop(L, 1);
+ lua_setfield(L, LUA_REGISTRYINDEX, MAXSTACKIDX);
+ return 0;
+}
+
+
+static int printpat_l (lua_State *L) {
+ Instruction *p = getpatt(L, 1, NULL);
+ int n, i;
+ lua_getfenv(L, 1);
+ n = ktablelen(L, -1);
+ printf("[");
+ for (i = 1; i <= n; i++) {
+ printf("%d = ", i);
+ lua_rawgeti(L, -1, i);
+ if (lua_isstring(L, -1))
+ printf("%s ", lua_tostring(L, -1));
+ else
+ printf("%s ", lua_typename(L, lua_type(L, -1)));
+ lua_pop(L, 1);
+ }
+ printf("]\n");
+ printpatt(p);
+ return 0;
+}
+
+
+static int matchl (lua_State *L) {
+ Capture capture[INITCAPSIZE];
+ const char *r;
+ size_t l;
+ Instruction *p = getpatt(L, 1, NULL);
+ const char *s = luaL_checklstring(L, SUBJIDX, &l);
+ int ptop = lua_gettop(L);
+ lua_Integer ii = luaL_optinteger(L, 3, 1);
+ size_t i = (ii > 0) ?
+ (((size_t)ii <= l) ? (size_t)ii - 1 : l) :
+ (((size_t)-ii <= l) ? l - ((size_t)-ii) : 0);
+ lua_pushnil(L); /* subscache */
+ lua_pushlightuserdata(L, capture); /* caplistidx */
+ lua_getfenv(L, 1); /* penvidx */
+ r = match(L, s, s + i, s + l, p, capture, ptop);
+ if (r == NULL) {
+ lua_pushnil(L);
+ return 1;
+ }
+ return getcaptures(L, s, r, ptop);
+}
+
+
+static struct luaL_reg pattreg[] = {
+ {"match", matchl},
+ {"print", printpat_l},
+ {"locale", locale_l},
+ {"setmaxstack", setmax},
+ {"B", pattbehind},
+ {"C", capture_l},
+ {"Cf", fold_l},
+ {"Cc", capconst_l},
+ {"Cg", group_l},
+ {"Cp", position_l},
+ {"Cb", backref_l},
+ {"Carg", argcap_l},
+ {"Cmt", matchtime_l},
+ {"Cs", capsubst_l},
+ {"Ct", tcapture_l},
+ {"P", pattern_l},
+ {"R", range_l},
+ {"S", set_l},
+ {"V", nter_l},
+ {"type", type_l},
+ {"version", version_l},
+ {NULL, NULL}
+};
+
+
+static struct luaL_reg metapattreg[] = {
+ {"__add", union_l},
+ {"__pow", star_l},
+ {"__sub", diff_l},
+ {"__mul", concat_l},
+ {"__div", rcapture_l},
+ {"__unm", unm_l},
+ {"__len", pattand_l},
+ {NULL, NULL}
+};
+
+
+int luaopen_lpeg (lua_State *L);
+int luaopen_lpeg (lua_State *L) {
+ lua_pushcfunction(L, (lua_CFunction)&l_newpf); /* new-pattern function */
+ lua_setfield(L, LUA_REGISTRYINDEX, KEYNEWPATT); /* register it */
+ luaL_newmetatable(L, PATTERN_T);
+ lua_pushnumber(L, MAXBACK);
+ lua_setfield(L, LUA_REGISTRYINDEX, MAXSTACKIDX);
+ luaL_register(L, NULL, metapattreg);
+ luaL_register(L, "lpeg", pattreg);
+ lua_pushliteral(L, "__index");
+ lua_pushvalue(L, -2);
+ lua_settable(L, -4);
+ return 1;
+}
+
diff --git a/aegisub/src/lpeg.h b/aegisub/src/lpeg.h
new file mode 100644
index 000000000..13d7acefd
--- /dev/null
+++ b/aegisub/src/lpeg.h
@@ -0,0 +1,38 @@
+/*
+** $Id: lpeg.h,v 1.1 2009/12/23 16:15:36 roberto Exp $
+** LPeg - PEG pattern matching for Lua
+** Copyright 2009, Lua.org & PUC-Rio (see 'lpeg.html' for license)
+** written by Roberto Ierusalimschy
+*/
+
+#ifndef lpeg_h
+#define lpeg_h
+
+#include "lua.h"
+
+
+#define KEYNEWPATT "lpeg.newpf"
+
+
+/*
+** type of extension functions that define new "patterns" for LPEG
+** It should return the new current position or NULL if match fails
+*/
+typedef const char *(*PattFunc) (const char *s, /* current position */
+ const char *e, /* string end */
+ const char *o, /* string start */
+ const void *ud); /* user data */
+
+/*
+** function to create new patterns based on 'PattFunc' functions.
+** This function is available at *registry[KEYNEWPATT]. (Notice
+** the extra indirection; the userdata at the registry points to
+** a variable that points to the function. In ANSI C a void* cannot
+** point to a function.)
+*/
+typedef void (*Newpf) (lua_State *L,
+ PattFunc f, /* pattern */
+ const void *ud, /* (user) data to be passed to 'f' */
+ size_t l); /* size of data to be passed to 'f' */
+
+#endif