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-rw-r--r--lua-5.3.5/lstrlib.c1584
1 files changed, 1584 insertions, 0 deletions
diff --git a/lua-5.3.5/lstrlib.c b/lua-5.3.5/lstrlib.c
new file mode 100644
index 0000000..b4bed7e
--- /dev/null
+++ b/lua-5.3.5/lstrlib.c
@@ -0,0 +1,1584 @@
+/*
+** $Id: lstrlib.c,v 1.254.1.1 2017/04/19 17:29:57 roberto Exp $
+** Standard library for string operations and pattern-matching
+** See Copyright Notice in lua.h
+*/
+
+#define lstrlib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <ctype.h>
+#include <float.h>
+#include <limits.h>
+#include <locale.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/*
+** maximum number of captures that a pattern can do during
+** pattern-matching. This limit is arbitrary, but must fit in
+** an unsigned char.
+*/
+#if !defined(LUA_MAXCAPTURES)
+#define LUA_MAXCAPTURES 32
+#endif
+
+
+/* macro to 'unsign' a character */
+#define uchar(c) ((unsigned char)(c))
+
+
+/*
+** Some sizes are better limited to fit in 'int', but must also fit in
+** 'size_t'. (We assume that 'lua_Integer' cannot be smaller than 'int'.)
+*/
+#define MAX_SIZET ((size_t)(~(size_t)0))
+
+#define MAXSIZE \
+ (sizeof(size_t) < sizeof(int) ? MAX_SIZET : (size_t)(INT_MAX))
+
+
+
+
+static int str_len (lua_State *L) {
+ size_t l;
+ luaL_checklstring(L, 1, &l);
+ lua_pushinteger(L, (lua_Integer)l);
+ return 1;
+}
+
+
+/* translate a relative string position: negative means back from end */
+static lua_Integer posrelat (lua_Integer pos, size_t len) {
+ if (pos >= 0) return pos;
+ else if (0u - (size_t)pos > len) return 0;
+ else return (lua_Integer)len + pos + 1;
+}
+
+
+static int str_sub (lua_State *L) {
+ size_t l;
+ const char *s = luaL_checklstring(L, 1, &l);
+ lua_Integer start = posrelat(luaL_checkinteger(L, 2), l);
+ lua_Integer end = posrelat(luaL_optinteger(L, 3, -1), l);
+ if (start < 1) start = 1;
+ if (end > (lua_Integer)l) end = l;
+ if (start <= end)
+ lua_pushlstring(L, s + start - 1, (size_t)(end - start) + 1);
+ else lua_pushliteral(L, "");
+ return 1;
+}
+
+
+static int str_reverse (lua_State *L) {
+ size_t l, i;
+ luaL_Buffer b;
+ const char *s = luaL_checklstring(L, 1, &l);
+ char *p = luaL_buffinitsize(L, &b, l);
+ for (i = 0; i < l; i++)
+ p[i] = s[l - i - 1];
+ luaL_pushresultsize(&b, l);
+ return 1;
+}
+
+
+static int str_lower (lua_State *L) {
+ size_t l;
+ size_t i;
+ luaL_Buffer b;
+ const char *s = luaL_checklstring(L, 1, &l);
+ char *p = luaL_buffinitsize(L, &b, l);
+ for (i=0; i<l; i++)
+ p[i] = tolower(uchar(s[i]));
+ luaL_pushresultsize(&b, l);
+ return 1;
+}
+
+
+static int str_upper (lua_State *L) {
+ size_t l;
+ size_t i;
+ luaL_Buffer b;
+ const char *s = luaL_checklstring(L, 1, &l);
+ char *p = luaL_buffinitsize(L, &b, l);
+ for (i=0; i<l; i++)
+ p[i] = toupper(uchar(s[i]));
+ luaL_pushresultsize(&b, l);
+ return 1;
+}
+
+
+static int str_rep (lua_State *L) {
+ size_t l, lsep;
+ const char *s = luaL_checklstring(L, 1, &l);
+ lua_Integer n = luaL_checkinteger(L, 2);
+ const char *sep = luaL_optlstring(L, 3, "", &lsep);
+ if (n <= 0) lua_pushliteral(L, "");
+ else if (l + lsep < l || l + lsep > MAXSIZE / n) /* may overflow? */
+ return luaL_error(L, "resulting string too large");
+ else {
+ size_t totallen = (size_t)n * l + (size_t)(n - 1) * lsep;
+ luaL_Buffer b;
+ char *p = luaL_buffinitsize(L, &b, totallen);
+ while (n-- > 1) { /* first n-1 copies (followed by separator) */
+ memcpy(p, s, l * sizeof(char)); p += l;
+ if (lsep > 0) { /* empty 'memcpy' is not that cheap */
+ memcpy(p, sep, lsep * sizeof(char));
+ p += lsep;
+ }
+ }
+ memcpy(p, s, l * sizeof(char)); /* last copy (not followed by separator) */
+ luaL_pushresultsize(&b, totallen);
+ }
+ return 1;
+}
+
+
+static int str_byte (lua_State *L) {
+ size_t l;
+ const char *s = luaL_checklstring(L, 1, &l);
+ lua_Integer posi = posrelat(luaL_optinteger(L, 2, 1), l);
+ lua_Integer pose = posrelat(luaL_optinteger(L, 3, posi), l);
+ int n, i;
+ if (posi < 1) posi = 1;
+ if (pose > (lua_Integer)l) pose = l;
+ if (posi > pose) return 0; /* empty interval; return no values */
+ if (pose - posi >= INT_MAX) /* arithmetic overflow? */
+ return luaL_error(L, "string slice too long");
+ n = (int)(pose - posi) + 1;
+ luaL_checkstack(L, n, "string slice too long");
+ for (i=0; i<n; i++)
+ lua_pushinteger(L, uchar(s[posi+i-1]));
+ return n;
+}
+
+
+static int str_char (lua_State *L) {
+ int n = lua_gettop(L); /* number of arguments */
+ int i;
+ luaL_Buffer b;
+ char *p = luaL_buffinitsize(L, &b, n);
+ for (i=1; i<=n; i++) {
+ lua_Integer c = luaL_checkinteger(L, i);
+ luaL_argcheck(L, uchar(c) == c, i, "value out of range");
+ p[i - 1] = uchar(c);
+ }
+ luaL_pushresultsize(&b, n);
+ return 1;
+}
+
+
+static int writer (lua_State *L, const void *b, size_t size, void *B) {
+ (void)L;
+ luaL_addlstring((luaL_Buffer *) B, (const char *)b, size);
+ return 0;
+}
+
+
+static int str_dump (lua_State *L) {
+ luaL_Buffer b;
+ int strip = lua_toboolean(L, 2);
+ luaL_checktype(L, 1, LUA_TFUNCTION);
+ lua_settop(L, 1);
+ luaL_buffinit(L,&b);
+ if (lua_dump(L, writer, &b, strip) != 0)
+ return luaL_error(L, "unable to dump given function");
+ luaL_pushresult(&b);
+ return 1;
+}
+
+
+
+/*
+** {======================================================
+** PATTERN MATCHING
+** =======================================================
+*/
+
+
+#define CAP_UNFINISHED (-1)
+#define CAP_POSITION (-2)
+
+
+typedef struct MatchState {
+ const char *src_init; /* init of source string */
+ const char *src_end; /* end ('\0') of source string */
+ const char *p_end; /* end ('\0') of pattern */
+ lua_State *L;
+ int matchdepth; /* control for recursive depth (to avoid C stack overflow) */
+ unsigned char level; /* total number of captures (finished or unfinished) */
+ struct {
+ const char *init;
+ ptrdiff_t len;
+ } capture[LUA_MAXCAPTURES];
+} MatchState;
+
+
+/* recursive function */
+static const char *match (MatchState *ms, const char *s, const char *p);
+
+
+/* maximum recursion depth for 'match' */
+#if !defined(MAXCCALLS)
+#define MAXCCALLS 200
+#endif
+
+
+#define L_ESC '%'
+#define SPECIALS "^$*+?.([%-"
+
+
+static int check_capture (MatchState *ms, int l) {
+ l -= '1';
+ if (l < 0 || l >= ms->level || ms->capture[l].len == CAP_UNFINISHED)
+ return luaL_error(ms->L, "invalid capture index %%%d", l + 1);
+ return l;
+}
+
+
+static int capture_to_close (MatchState *ms) {
+ int level = ms->level;
+ for (level--; level>=0; level--)
+ if (ms->capture[level].len == CAP_UNFINISHED) return level;
+ return luaL_error(ms->L, "invalid pattern capture");
+}
+
+
+static const char *classend (MatchState *ms, const char *p) {
+ switch (*p++) {
+ case L_ESC: {
+ if (p == ms->p_end)
+ luaL_error(ms->L, "malformed pattern (ends with '%%')");
+ return p+1;
+ }
+ case '[': {
+ if (*p == '^') p++;
+ do { /* look for a ']' */
+ if (p == ms->p_end)
+ luaL_error(ms->L, "malformed pattern (missing ']')");
+ if (*(p++) == L_ESC && p < ms->p_end)
+ p++; /* skip escapes (e.g. '%]') */
+ } while (*p != ']');
+ return p+1;
+ }
+ default: {
+ return p;
+ }
+ }
+}
+
+
+static int match_class (int c, int cl) {
+ int res;
+ switch (tolower(cl)) {
+ case 'a' : res = isalpha(c); break;
+ case 'c' : res = iscntrl(c); break;
+ case 'd' : res = isdigit(c); break;
+ case 'g' : res = isgraph(c); break;
+ case 'l' : res = islower(c); break;
+ case 'p' : res = ispunct(c); break;
+ case 's' : res = isspace(c); break;
+ case 'u' : res = isupper(c); break;
+ case 'w' : res = isalnum(c); break;
+ case 'x' : res = isxdigit(c); break;
+ case 'z' : res = (c == 0); break; /* deprecated option */
+ default: return (cl == c);
+ }
+ return (islower(cl) ? res : !res);
+}
+
+
+static int matchbracketclass (int c, const char *p, const char *ec) {
+ int sig = 1;
+ if (*(p+1) == '^') {
+ sig = 0;
+ p++; /* skip the '^' */
+ }
+ while (++p < ec) {
+ if (*p == L_ESC) {
+ p++;
+ if (match_class(c, uchar(*p)))
+ return sig;
+ }
+ else if ((*(p+1) == '-') && (p+2 < ec)) {
+ p+=2;
+ if (uchar(*(p-2)) <= c && c <= uchar(*p))
+ return sig;
+ }
+ else if (uchar(*p) == c) return sig;
+ }
+ return !sig;
+}
+
+
+static int singlematch (MatchState *ms, const char *s, const char *p,
+ const char *ep) {
+ if (s >= ms->src_end)
+ return 0;
+ else {
+ int c = uchar(*s);
+ switch (*p) {
+ case '.': return 1; /* matches any char */
+ case L_ESC: return match_class(c, uchar(*(p+1)));
+ case '[': return matchbracketclass(c, p, ep-1);
+ default: return (uchar(*p) == c);
+ }
+ }
+}
+
+
+static const char *matchbalance (MatchState *ms, const char *s,
+ const char *p) {
+ if (p >= ms->p_end - 1)
+ luaL_error(ms->L, "malformed pattern (missing arguments to '%%b')");
+ if (*s != *p) return NULL;
+ else {
+ int b = *p;
+ int e = *(p+1);
+ int cont = 1;
+ while (++s < ms->src_end) {
+ if (*s == e) {
+ if (--cont == 0) return s+1;
+ }
+ else if (*s == b) cont++;
+ }
+ }
+ return NULL; /* string ends out of balance */
+}
+
+
+static const char *max_expand (MatchState *ms, const char *s,
+ const char *p, const char *ep) {
+ ptrdiff_t i = 0; /* counts maximum expand for item */
+ while (singlematch(ms, s + i, p, ep))
+ i++;
+ /* keeps trying to match with the maximum repetitions */
+ while (i>=0) {
+ const char *res = match(ms, (s+i), ep+1);
+ if (res) return res;
+ i--; /* else didn't match; reduce 1 repetition to try again */
+ }
+ return NULL;
+}
+
+
+static const char *min_expand (MatchState *ms, const char *s,
+ const char *p, const char *ep) {
+ for (;;) {
+ const char *res = match(ms, s, ep+1);
+ if (res != NULL)
+ return res;
+ else if (singlematch(ms, s, p, ep))
+ s++; /* try with one more repetition */
+ else return NULL;
+ }
+}
+
+
+static const char *start_capture (MatchState *ms, const char *s,
+ const char *p, int what) {
+ const char *res;
+ int level = ms->level;
+ if (level >= LUA_MAXCAPTURES) luaL_error(ms->L, "too many captures");
+ ms->capture[level].init = s;
+ ms->capture[level].len = what;
+ ms->level = level+1;
+ if ((res=match(ms, s, p)) == NULL) /* match failed? */
+ ms->level--; /* undo capture */
+ return res;
+}
+
+
+static const char *end_capture (MatchState *ms, const char *s,
+ const char *p) {
+ int l = capture_to_close(ms);
+ const char *res;
+ ms->capture[l].len = s - ms->capture[l].init; /* close capture */
+ if ((res = match(ms, s, p)) == NULL) /* match failed? */
+ ms->capture[l].len = CAP_UNFINISHED; /* undo capture */
+ return res;
+}
+
+
+static const char *match_capture (MatchState *ms, const char *s, int l) {
+ size_t len;
+ l = check_capture(ms, l);
+ len = ms->capture[l].len;
+ if ((size_t)(ms->src_end-s) >= len &&
+ memcmp(ms->capture[l].init, s, len) == 0)
+ return s+len;
+ else return NULL;
+}
+
+
+static const char *match (MatchState *ms, const char *s, const char *p) {
+ if (ms->matchdepth-- == 0)
+ luaL_error(ms->L, "pattern too complex");
+ init: /* using goto's to optimize tail recursion */
+ if (p != ms->p_end) { /* end of pattern? */
+ switch (*p) {
+ case '(': { /* start capture */
+ if (*(p + 1) == ')') /* position capture? */
+ s = start_capture(ms, s, p + 2, CAP_POSITION);
+ else
+ s = start_capture(ms, s, p + 1, CAP_UNFINISHED);
+ break;
+ }
+ case ')': { /* end capture */
+ s = end_capture(ms, s, p + 1);
+ break;
+ }
+ case '$': {
+ if ((p + 1) != ms->p_end) /* is the '$' the last char in pattern? */
+ goto dflt; /* no; go to default */
+ s = (s == ms->src_end) ? s : NULL; /* check end of string */
+ break;
+ }
+ case L_ESC: { /* escaped sequences not in the format class[*+?-]? */
+ switch (*(p + 1)) {
+ case 'b': { /* balanced string? */
+ s = matchbalance(ms, s, p + 2);
+ if (s != NULL) {
+ p += 4; goto init; /* return match(ms, s, p + 4); */
+ } /* else fail (s == NULL) */
+ break;
+ }
+ case 'f': { /* frontier? */
+ const char *ep; char previous;
+ p += 2;
+ if (*p != '[')
+ luaL_error(ms->L, "missing '[' after '%%f' in pattern");
+ ep = classend(ms, p); /* points to what is next */
+ previous = (s == ms->src_init) ? '\0' : *(s - 1);
+ if (!matchbracketclass(uchar(previous), p, ep - 1) &&
+ matchbracketclass(uchar(*s), p, ep - 1)) {
+ p = ep; goto init; /* return match(ms, s, ep); */
+ }
+ s = NULL; /* match failed */
+ break;
+ }
+ case '0': case '1': case '2': case '3':
+ case '4': case '5': case '6': case '7':
+ case '8': case '9': { /* capture results (%0-%9)? */
+ s = match_capture(ms, s, uchar(*(p + 1)));
+ if (s != NULL) {
+ p += 2; goto init; /* return match(ms, s, p + 2) */
+ }
+ break;
+ }
+ default: goto dflt;
+ }
+ break;
+ }
+ default: dflt: { /* pattern class plus optional suffix */
+ const char *ep = classend(ms, p); /* points to optional suffix */
+ /* does not match at least once? */
+ if (!singlematch(ms, s, p, ep)) {
+ if (*ep == '*' || *ep == '?' || *ep == '-') { /* accept empty? */
+ p = ep + 1; goto init; /* return match(ms, s, ep + 1); */
+ }
+ else /* '+' or no suffix */
+ s = NULL; /* fail */
+ }
+ else { /* matched once */
+ switch (*ep) { /* handle optional suffix */
+ case '?': { /* optional */
+ const char *res;
+ if ((res = match(ms, s + 1, ep + 1)) != NULL)
+ s = res;
+ else {
+ p = ep + 1; goto init; /* else return match(ms, s, ep + 1); */
+ }
+ break;
+ }
+ case '+': /* 1 or more repetitions */
+ s++; /* 1 match already done */
+ /* FALLTHROUGH */
+ case '*': /* 0 or more repetitions */
+ s = max_expand(ms, s, p, ep);
+ break;
+ case '-': /* 0 or more repetitions (minimum) */
+ s = min_expand(ms, s, p, ep);
+ break;
+ default: /* no suffix */
+ s++; p = ep; goto init; /* return match(ms, s + 1, ep); */
+ }
+ }
+ break;
+ }
+ }
+ }
+ ms->matchdepth++;
+ return s;
+}
+
+
+
+static const char *lmemfind (const char *s1, size_t l1,
+ const char *s2, size_t l2) {
+ if (l2 == 0) return s1; /* empty strings are everywhere */
+ else if (l2 > l1) return NULL; /* avoids a negative 'l1' */
+ else {
+ const char *init; /* to search for a '*s2' inside 's1' */
+ l2--; /* 1st char will be checked by 'memchr' */
+ l1 = l1-l2; /* 's2' cannot be found after that */
+ while (l1 > 0 && (init = (const char *)memchr(s1, *s2, l1)) != NULL) {
+ init++; /* 1st char is already checked */
+ if (memcmp(init, s2+1, l2) == 0)
+ return init-1;
+ else { /* correct 'l1' and 's1' to try again */
+ l1 -= init-s1;
+ s1 = init;
+ }
+ }
+ return NULL; /* not found */
+ }
+}
+
+
+static void push_onecapture (MatchState *ms, int i, const char *s,
+ const char *e) {
+ if (i >= ms->level) {
+ if (i == 0) /* ms->level == 0, too */
+ lua_pushlstring(ms->L, s, e - s); /* add whole match */
+ else
+ luaL_error(ms->L, "invalid capture index %%%d", i + 1);
+ }
+ else {
+ ptrdiff_t l = ms->capture[i].len;
+ if (l == CAP_UNFINISHED) luaL_error(ms->L, "unfinished capture");
+ if (l == CAP_POSITION)
+ lua_pushinteger(ms->L, (ms->capture[i].init - ms->src_init) + 1);
+ else
+ lua_pushlstring(ms->L, ms->capture[i].init, l);
+ }
+}
+
+
+static int push_captures (MatchState *ms, const char *s, const char *e) {
+ int i;
+ int nlevels = (ms->level == 0 && s) ? 1 : ms->level;
+ luaL_checkstack(ms->L, nlevels, "too many captures");
+ for (i = 0; i < nlevels; i++)
+ push_onecapture(ms, i, s, e);
+ return nlevels; /* number of strings pushed */
+}
+
+
+/* check whether pattern has no special characters */
+static int nospecials (const char *p, size_t l) {
+ size_t upto = 0;
+ do {
+ if (strpbrk(p + upto, SPECIALS))
+ return 0; /* pattern has a special character */
+ upto += strlen(p + upto) + 1; /* may have more after \0 */
+ } while (upto <= l);
+ return 1; /* no special chars found */
+}
+
+
+static void prepstate (MatchState *ms, lua_State *L,
+ const char *s, size_t ls, const char *p, size_t lp) {
+ ms->L = L;
+ ms->matchdepth = MAXCCALLS;
+ ms->src_init = s;
+ ms->src_end = s + ls;
+ ms->p_end = p + lp;
+}
+
+
+static void reprepstate (MatchState *ms) {
+ ms->level = 0;
+ lua_assert(ms->matchdepth == MAXCCALLS);
+}
+
+
+static int str_find_aux (lua_State *L, int find) {
+ size_t ls, lp;
+ const char *s = luaL_checklstring(L, 1, &ls);
+ const char *p = luaL_checklstring(L, 2, &lp);
+ lua_Integer init = posrelat(luaL_optinteger(L, 3, 1), ls);
+ if (init < 1) init = 1;
+ else if (init > (lua_Integer)ls + 1) { /* start after string's end? */
+ lua_pushnil(L); /* cannot find anything */
+ return 1;
+ }
+ /* explicit request or no special characters? */
+ if (find && (lua_toboolean(L, 4) || nospecials(p, lp))) {
+ /* do a plain search */
+ const char *s2 = lmemfind(s + init - 1, ls - (size_t)init + 1, p, lp);
+ if (s2) {
+ lua_pushinteger(L, (s2 - s) + 1);
+ lua_pushinteger(L, (s2 - s) + lp);
+ return 2;
+ }
+ }
+ else {
+ MatchState ms;
+ const char *s1 = s + init - 1;
+ int anchor = (*p == '^');
+ if (anchor) {
+ p++; lp--; /* skip anchor character */
+ }
+ prepstate(&ms, L, s, ls, p, lp);
+ do {
+ const char *res;
+ reprepstate(&ms);
+ if ((res=match(&ms, s1, p)) != NULL) {
+ if (find) {
+ lua_pushinteger(L, (s1 - s) + 1); /* start */
+ lua_pushinteger(L, res - s); /* end */
+ return push_captures(&ms, NULL, 0) + 2;
+ }
+ else
+ return push_captures(&ms, s1, res);
+ }
+ } while (s1++ < ms.src_end && !anchor);
+ }
+ lua_pushnil(L); /* not found */
+ return 1;
+}
+
+
+static int str_find (lua_State *L) {
+ return str_find_aux(L, 1);
+}
+
+
+static int str_match (lua_State *L) {
+ return str_find_aux(L, 0);
+}
+
+
+/* state for 'gmatch' */
+typedef struct GMatchState {
+ const char *src; /* current position */
+ const char *p; /* pattern */
+ const char *lastmatch; /* end of last match */
+ MatchState ms; /* match state */
+} GMatchState;
+
+
+static int gmatch_aux (lua_State *L) {
+ GMatchState *gm = (GMatchState *)lua_touserdata(L, lua_upvalueindex(3));
+ const char *src;
+ gm->ms.L = L;
+ for (src = gm->src; src <= gm->ms.src_end; src++) {
+ const char *e;
+ reprepstate(&gm->ms);
+ if ((e = match(&gm->ms, src, gm->p)) != NULL && e != gm->lastmatch) {
+ gm->src = gm->lastmatch = e;
+ return push_captures(&gm->ms, src, e);
+ }
+ }
+ return 0; /* not found */
+}
+
+
+static int gmatch (lua_State *L) {
+ size_t ls, lp;
+ const char *s = luaL_checklstring(L, 1, &ls);
+ const char *p = luaL_checklstring(L, 2, &lp);
+ GMatchState *gm;
+ lua_settop(L, 2); /* keep them on closure to avoid being collected */
+ gm = (GMatchState *)lua_newuserdata(L, sizeof(GMatchState));
+ prepstate(&gm->ms, L, s, ls, p, lp);
+ gm->src = s; gm->p = p; gm->lastmatch = NULL;
+ lua_pushcclosure(L, gmatch_aux, 3);
+ return 1;
+}
+
+
+static void add_s (MatchState *ms, luaL_Buffer *b, const char *s,
+ const char *e) {
+ size_t l, i;
+ lua_State *L = ms->L;
+ const char *news = lua_tolstring(L, 3, &l);
+ for (i = 0; i < l; i++) {
+ if (news[i] != L_ESC)
+ luaL_addchar(b, news[i]);
+ else {
+ i++; /* skip ESC */
+ if (!isdigit(uchar(news[i]))) {
+ if (news[i] != L_ESC)
+ luaL_error(L, "invalid use of '%c' in replacement string", L_ESC);
+ luaL_addchar(b, news[i]);
+ }
+ else if (news[i] == '0')
+ luaL_addlstring(b, s, e - s);
+ else {
+ push_onecapture(ms, news[i] - '1', s, e);
+ luaL_tolstring(L, -1, NULL); /* if number, convert it to string */
+ lua_remove(L, -2); /* remove original value */
+ luaL_addvalue(b); /* add capture to accumulated result */
+ }
+ }
+ }
+}
+
+
+static void add_value (MatchState *ms, luaL_Buffer *b, const char *s,
+ const char *e, int tr) {
+ lua_State *L = ms->L;
+ switch (tr) {
+ case LUA_TFUNCTION: {
+ int n;
+ lua_pushvalue(L, 3);
+ n = push_captures(ms, s, e);
+ lua_call(L, n, 1);
+ break;
+ }
+ case LUA_TTABLE: {
+ push_onecapture(ms, 0, s, e);
+ lua_gettable(L, 3);
+ break;
+ }
+ default: { /* LUA_TNUMBER or LUA_TSTRING */
+ add_s(ms, b, s, e);
+ return;
+ }
+ }
+ if (!lua_toboolean(L, -1)) { /* nil or false? */
+ lua_pop(L, 1);
+ lua_pushlstring(L, s, e - s); /* keep original text */
+ }
+ else if (!lua_isstring(L, -1))
+ luaL_error(L, "invalid replacement value (a %s)", luaL_typename(L, -1));
+ luaL_addvalue(b); /* add result to accumulator */
+}
+
+
+static int str_gsub (lua_State *L) {
+ size_t srcl, lp;
+ const char *src = luaL_checklstring(L, 1, &srcl); /* subject */
+ const char *p = luaL_checklstring(L, 2, &lp); /* pattern */
+ const char *lastmatch = NULL; /* end of last match */
+ int tr = lua_type(L, 3); /* replacement type */
+ lua_Integer max_s = luaL_optinteger(L, 4, srcl + 1); /* max replacements */
+ int anchor = (*p == '^');
+ lua_Integer n = 0; /* replacement count */
+ MatchState ms;
+ luaL_Buffer b;
+ luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
+ tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
+ "string/function/table expected");
+ luaL_buffinit(L, &b);
+ if (anchor) {
+ p++; lp--; /* skip anchor character */
+ }
+ prepstate(&ms, L, src, srcl, p, lp);
+ while (n < max_s) {
+ const char *e;
+ reprepstate(&ms); /* (re)prepare state for new match */
+ if ((e = match(&ms, src, p)) != NULL && e != lastmatch) { /* match? */
+ n++;
+ add_value(&ms, &b, src, e, tr); /* add replacement to buffer */
+ src = lastmatch = e;
+ }
+ else if (src < ms.src_end) /* otherwise, skip one character */
+ luaL_addchar(&b, *src++);
+ else break; /* end of subject */
+ if (anchor) break;
+ }
+ luaL_addlstring(&b, src, ms.src_end-src);
+ luaL_pushresult(&b);
+ lua_pushinteger(L, n); /* number of substitutions */
+ return 2;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** STRING FORMAT
+** =======================================================
+*/
+
+#if !defined(lua_number2strx) /* { */
+
+/*
+** Hexadecimal floating-point formatter
+*/
+
+#include <math.h>
+
+#define SIZELENMOD (sizeof(LUA_NUMBER_FRMLEN)/sizeof(char))
+
+
+/*
+** Number of bits that goes into the first digit. It can be any value
+** between 1 and 4; the following definition tries to align the number
+** to nibble boundaries by making what is left after that first digit a
+** multiple of 4.
+*/
+#define L_NBFD ((l_mathlim(MANT_DIG) - 1)%4 + 1)
+
+
+/*
+** Add integer part of 'x' to buffer and return new 'x'
+*/
+static lua_Number adddigit (char *buff, int n, lua_Number x) {
+ lua_Number dd = l_mathop(floor)(x); /* get integer part from 'x' */
+ int d = (int)dd;
+ buff[n] = (d < 10 ? d + '0' : d - 10 + 'a'); /* add to buffer */
+ return x - dd; /* return what is left */
+}
+
+
+static int num2straux (char *buff, int sz, lua_Number x) {
+ /* if 'inf' or 'NaN', format it like '%g' */
+ if (x != x || x == (lua_Number)HUGE_VAL || x == -(lua_Number)HUGE_VAL)
+ return l_sprintf(buff, sz, LUA_NUMBER_FMT, (LUAI_UACNUMBER)x);
+ else if (x == 0) { /* can be -0... */
+ /* create "0" or "-0" followed by exponent */
+ return l_sprintf(buff, sz, LUA_NUMBER_FMT "x0p+0", (LUAI_UACNUMBER)x);
+ }
+ else {
+ int e;
+ lua_Number m = l_mathop(frexp)(x, &e); /* 'x' fraction and exponent */
+ int n = 0; /* character count */
+ if (m < 0) { /* is number negative? */
+ buff[n++] = '-'; /* add signal */
+ m = -m; /* make it positive */
+ }
+ buff[n++] = '0'; buff[n++] = 'x'; /* add "0x" */
+ m = adddigit(buff, n++, m * (1 << L_NBFD)); /* add first digit */
+ e -= L_NBFD; /* this digit goes before the radix point */
+ if (m > 0) { /* more digits? */
+ buff[n++] = lua_getlocaledecpoint(); /* add radix point */
+ do { /* add as many digits as needed */
+ m = adddigit(buff, n++, m * 16);
+ } while (m > 0);
+ }
+ n += l_sprintf(buff + n, sz - n, "p%+d", e); /* add exponent */
+ lua_assert(n < sz);
+ return n;
+ }
+}
+
+
+static int lua_number2strx (lua_State *L, char *buff, int sz,
+ const char *fmt, lua_Number x) {
+ int n = num2straux(buff, sz, x);
+ if (fmt[SIZELENMOD] == 'A') {
+ int i;
+ for (i = 0; i < n; i++)
+ buff[i] = toupper(uchar(buff[i]));
+ }
+ else if (fmt[SIZELENMOD] != 'a')
+ return luaL_error(L, "modifiers for format '%%a'/'%%A' not implemented");
+ return n;
+}
+
+#endif /* } */
+
+
+/*
+** Maximum size of each formatted item. This maximum size is produced
+** by format('%.99f', -maxfloat), and is equal to 99 + 3 ('-', '.',
+** and '\0') + number of decimal digits to represent maxfloat (which
+** is maximum exponent + 1). (99+3+1 then rounded to 120 for "extra
+** expenses", such as locale-dependent stuff)
+*/
+#define MAX_ITEM (120 + l_mathlim(MAX_10_EXP))
+
+
+/* valid flags in a format specification */
+#define FLAGS "-+ #0"
+
+/*
+** maximum size of each format specification (such as "%-099.99d")
+*/
+#define MAX_FORMAT 32
+
+
+static void addquoted (luaL_Buffer *b, const char *s, size_t len) {
+ luaL_addchar(b, '"');
+ while (len--) {
+ if (*s == '"' || *s == '\\' || *s == '\n') {
+ luaL_addchar(b, '\\');
+ luaL_addchar(b, *s);
+ }
+ else if (iscntrl(uchar(*s))) {
+ char buff[10];
+ if (!isdigit(uchar(*(s+1))))
+ l_sprintf(buff, sizeof(buff), "\\%d", (int)uchar(*s));
+ else
+ l_sprintf(buff, sizeof(buff), "\\%03d", (int)uchar(*s));
+ luaL_addstring(b, buff);
+ }
+ else
+ luaL_addchar(b, *s);
+ s++;
+ }
+ luaL_addchar(b, '"');
+}
+
+
+/*
+** Ensures the 'buff' string uses a dot as the radix character.
+*/
+static void checkdp (char *buff, int nb) {
+ if (memchr(buff, '.', nb) == NULL) { /* no dot? */
+ char point = lua_getlocaledecpoint(); /* try locale point */
+ char *ppoint = (char *)memchr(buff, point, nb);
+ if (ppoint) *ppoint = '.'; /* change it to a dot */
+ }
+}
+
+
+static void addliteral (lua_State *L, luaL_Buffer *b, int arg) {
+ switch (lua_type(L, arg)) {
+ case LUA_TSTRING: {
+ size_t len;
+ const char *s = lua_tolstring(L, arg, &len);
+ addquoted(b, s, len);
+ break;
+ }
+ case LUA_TNUMBER: {
+ char *buff = luaL_prepbuffsize(b, MAX_ITEM);
+ int nb;
+ if (!lua_isinteger(L, arg)) { /* float? */
+ lua_Number n = lua_tonumber(L, arg); /* write as hexa ('%a') */
+ nb = lua_number2strx(L, buff, MAX_ITEM, "%" LUA_NUMBER_FRMLEN "a", n);
+ checkdp(buff, nb); /* ensure it uses a dot */
+ }
+ else { /* integers */
+ lua_Integer n = lua_tointeger(L, arg);
+ const char *format = (n == LUA_MININTEGER) /* corner case? */
+ ? "0x%" LUA_INTEGER_FRMLEN "x" /* use hexa */
+ : LUA_INTEGER_FMT; /* else use default format */
+ nb = l_sprintf(buff, MAX_ITEM, format, (LUAI_UACINT)n);
+ }
+ luaL_addsize(b, nb);
+ break;
+ }
+ case LUA_TNIL: case LUA_TBOOLEAN: {
+ luaL_tolstring(L, arg, NULL);
+ luaL_addvalue(b);
+ break;
+ }
+ default: {
+ luaL_argerror(L, arg, "value has no literal form");
+ }
+ }
+}
+
+
+static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
+ const char *p = strfrmt;
+ while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++; /* skip flags */
+ if ((size_t)(p - strfrmt) >= sizeof(FLAGS)/sizeof(char))
+ luaL_error(L, "invalid format (repeated flags)");
+ if (isdigit(uchar(*p))) p++; /* skip width */
+ if (isdigit(uchar(*p))) p++; /* (2 digits at most) */
+ if (*p == '.') {
+ p++;
+ if (isdigit(uchar(*p))) p++; /* skip precision */
+ if (isdigit(uchar(*p))) p++; /* (2 digits at most) */
+ }
+ if (isdigit(uchar(*p)))
+ luaL_error(L, "invalid format (width or precision too long)");
+ *(form++) = '%';
+ memcpy(form, strfrmt, ((p - strfrmt) + 1) * sizeof(char));
+ form += (p - strfrmt) + 1;
+ *form = '\0';
+ return p;
+}
+
+
+/*
+** add length modifier into formats
+*/
+static void addlenmod (char *form, const char *lenmod) {
+ size_t l = strlen(form);
+ size_t lm = strlen(lenmod);
+ char spec = form[l - 1];
+ strcpy(form + l - 1, lenmod);
+ form[l + lm - 1] = spec;
+ form[l + lm] = '\0';
+}
+
+
+static int str_format (lua_State *L) {
+ int top = lua_gettop(L);
+ int arg = 1;
+ size_t sfl;
+ const char *strfrmt = luaL_checklstring(L, arg, &sfl);
+ const char *strfrmt_end = strfrmt+sfl;
+ luaL_Buffer b;
+ luaL_buffinit(L, &b);
+ while (strfrmt < strfrmt_end) {
+ if (*strfrmt != L_ESC)
+ luaL_addchar(&b, *strfrmt++);
+ else if (*++strfrmt == L_ESC)
+ luaL_addchar(&b, *strfrmt++); /* %% */
+ else { /* format item */
+ char form[MAX_FORMAT]; /* to store the format ('%...') */
+ char *buff = luaL_prepbuffsize(&b, MAX_ITEM); /* to put formatted item */
+ int nb = 0; /* number of bytes in added item */
+ if (++arg > top)
+ luaL_argerror(L, arg, "no value");
+ strfrmt = scanformat(L, strfrmt, form);
+ switch (*strfrmt++) {
+ case 'c': {
+ nb = l_sprintf(buff, MAX_ITEM, form, (int)luaL_checkinteger(L, arg));
+ break;
+ }
+ case 'd': case 'i':
+ case 'o': case 'u': case 'x': case 'X': {
+ lua_Integer n = luaL_checkinteger(L, arg);
+ addlenmod(form, LUA_INTEGER_FRMLEN);
+ nb = l_sprintf(buff, MAX_ITEM, form, (LUAI_UACINT)n);
+ break;
+ }
+ case 'a': case 'A':
+ addlenmod(form, LUA_NUMBER_FRMLEN);
+ nb = lua_number2strx(L, buff, MAX_ITEM, form,
+ luaL_checknumber(L, arg));
+ break;
+ case 'e': case 'E': case 'f':
+ case 'g': case 'G': {
+ lua_Number n = luaL_checknumber(L, arg);
+ addlenmod(form, LUA_NUMBER_FRMLEN);
+ nb = l_sprintf(buff, MAX_ITEM, form, (LUAI_UACNUMBER)n);
+ break;
+ }
+ case 'q': {
+ addliteral(L, &b, arg);
+ break;
+ }
+ case 's': {
+ size_t l;
+ const char *s = luaL_tolstring(L, arg, &l);
+ if (form[2] == '\0') /* no modifiers? */
+ luaL_addvalue(&b); /* keep entire string */
+ else {
+ luaL_argcheck(L, l == strlen(s), arg, "string contains zeros");
+ if (!strchr(form, '.') && l >= 100) {
+ /* no precision and string is too long to be formatted */
+ luaL_addvalue(&b); /* keep entire string */
+ }
+ else { /* format the string into 'buff' */
+ nb = l_sprintf(buff, MAX_ITEM, form, s);
+ lua_pop(L, 1); /* remove result from 'luaL_tolstring' */
+ }
+ }
+ break;
+ }
+ default: { /* also treat cases 'pnLlh' */
+ return luaL_error(L, "invalid option '%%%c' to 'format'",
+ *(strfrmt - 1));
+ }
+ }
+ lua_assert(nb < MAX_ITEM);
+ luaL_addsize(&b, nb);
+ }
+ }
+ luaL_pushresult(&b);
+ return 1;
+}
+
+/* }====================================================== */
+
+
+/*
+** {======================================================
+** PACK/UNPACK
+** =======================================================
+*/
+
+
+/* value used for padding */
+#if !defined(LUAL_PACKPADBYTE)
+#define LUAL_PACKPADBYTE 0x00
+#endif
+
+/* maximum size for the binary representation of an integer */
+#define MAXINTSIZE 16
+
+/* number of bits in a character */
+#define NB CHAR_BIT
+
+/* mask for one character (NB 1's) */
+#define MC ((1 << NB) - 1)
+
+/* size of a lua_Integer */
+#define SZINT ((int)sizeof(lua_Integer))
+
+
+/* dummy union to get native endianness */
+static const union {
+ int dummy;
+ char little; /* true iff machine is little endian */
+} nativeendian = {1};
+
+
+/* dummy structure to get native alignment requirements */
+struct cD {
+ char c;
+ union { double d; void *p; lua_Integer i; lua_Number n; } u;
+};
+
+#define MAXALIGN (offsetof(struct cD, u))
+
+
+/*
+** Union for serializing floats
+*/
+typedef union Ftypes {
+ float f;
+ double d;
+ lua_Number n;
+ char buff[5 * sizeof(lua_Number)]; /* enough for any float type */
+} Ftypes;
+
+
+/*
+** information to pack/unpack stuff
+*/
+typedef struct Header {
+ lua_State *L;
+ int islittle;
+ int maxalign;
+} Header;
+
+
+/*
+** options for pack/unpack
+*/
+typedef enum KOption {
+ Kint, /* signed integers */
+ Kuint, /* unsigned integers */
+ Kfloat, /* floating-point numbers */
+ Kchar, /* fixed-length strings */
+ Kstring, /* strings with prefixed length */
+ Kzstr, /* zero-terminated strings */
+ Kpadding, /* padding */
+ Kpaddalign, /* padding for alignment */
+ Knop /* no-op (configuration or spaces) */
+} KOption;
+
+
+/*
+** Read an integer numeral from string 'fmt' or return 'df' if
+** there is no numeral
+*/
+static int digit (int c) { return '0' <= c && c <= '9'; }
+
+static int getnum (const char **fmt, int df) {
+ if (!digit(**fmt)) /* no number? */
+ return df; /* return default value */
+ else {
+ int a = 0;
+ do {
+ a = a*10 + (*((*fmt)++) - '0');
+ } while (digit(**fmt) && a <= ((int)MAXSIZE - 9)/10);
+ return a;
+ }
+}
+
+
+/*
+** Read an integer numeral and raises an error if it is larger
+** than the maximum size for integers.
+*/
+static int getnumlimit (Header *h, const char **fmt, int df) {
+ int sz = getnum(fmt, df);
+ if (sz > MAXINTSIZE || sz <= 0)
+ return luaL_error(h->L, "integral size (%d) out of limits [1,%d]",
+ sz, MAXINTSIZE);
+ return sz;
+}
+
+
+/*
+** Initialize Header
+*/
+static void initheader (lua_State *L, Header *h) {
+ h->L = L;
+ h->islittle = nativeendian.little;
+ h->maxalign = 1;
+}
+
+
+/*
+** Read and classify next option. 'size' is filled with option's size.
+*/
+static KOption getoption (Header *h, const char **fmt, int *size) {
+ int opt = *((*fmt)++);
+ *size = 0; /* default */
+ switch (opt) {
+ case 'b': *size = sizeof(char); return Kint;
+ case 'B': *size = sizeof(char); return Kuint;
+ case 'h': *size = sizeof(short); return Kint;
+ case 'H': *size = sizeof(short); return Kuint;
+ case 'l': *size = sizeof(long); return Kint;
+ case 'L': *size = sizeof(long); return Kuint;
+ case 'j': *size = sizeof(lua_Integer); return Kint;
+ case 'J': *size = sizeof(lua_Integer); return Kuint;
+ case 'T': *size = sizeof(size_t); return Kuint;
+ case 'f': *size = sizeof(float); return Kfloat;
+ case 'd': *size = sizeof(double); return Kfloat;
+ case 'n': *size = sizeof(lua_Number); return Kfloat;
+ case 'i': *size = getnumlimit(h, fmt, sizeof(int)); return Kint;
+ case 'I': *size = getnumlimit(h, fmt, sizeof(int)); return Kuint;
+ case 's': *size = getnumlimit(h, fmt, sizeof(size_t)); return Kstring;
+ case 'c':
+ *size = getnum(fmt, -1);
+ if (*size == -1)
+ luaL_error(h->L, "missing size for format option 'c'");
+ return Kchar;
+ case 'z': return Kzstr;
+ case 'x': *size = 1; return Kpadding;
+ case 'X': return Kpaddalign;
+ case ' ': break;
+ case '<': h->islittle = 1; break;
+ case '>': h->islittle = 0; break;
+ case '=': h->islittle = nativeendian.little; break;
+ case '!': h->maxalign = getnumlimit(h, fmt, MAXALIGN); break;
+ default: luaL_error(h->L, "invalid format option '%c'", opt);
+ }
+ return Knop;
+}
+
+
+/*
+** Read, classify, and fill other details about the next option.
+** 'psize' is filled with option's size, 'notoalign' with its
+** alignment requirements.
+** Local variable 'size' gets the size to be aligned. (Kpadal option
+** always gets its full alignment, other options are limited by
+** the maximum alignment ('maxalign'). Kchar option needs no alignment
+** despite its size.
+*/
+static KOption getdetails (Header *h, size_t totalsize,
+ const char **fmt, int *psize, int *ntoalign) {
+ KOption opt = getoption(h, fmt, psize);
+ int align = *psize; /* usually, alignment follows size */
+ if (opt == Kpaddalign) { /* 'X' gets alignment from following option */
+ if (**fmt == '\0' || getoption(h, fmt, &align) == Kchar || align == 0)
+ luaL_argerror(h->L, 1, "invalid next option for option 'X'");
+ }
+ if (align <= 1 || opt == Kchar) /* need no alignment? */
+ *ntoalign = 0;
+ else {
+ if (align > h->maxalign) /* enforce maximum alignment */
+ align = h->maxalign;
+ if ((align & (align - 1)) != 0) /* is 'align' not a power of 2? */
+ luaL_argerror(h->L, 1, "format asks for alignment not power of 2");
+ *ntoalign = (align - (int)(totalsize & (align - 1))) & (align - 1);
+ }
+ return opt;
+}
+
+
+/*
+** Pack integer 'n' with 'size' bytes and 'islittle' endianness.
+** The final 'if' handles the case when 'size' is larger than
+** the size of a Lua integer, correcting the extra sign-extension
+** bytes if necessary (by default they would be zeros).
+*/
+static void packint (luaL_Buffer *b, lua_Unsigned n,
+ int islittle, int size, int neg) {
+ char *buff = luaL_prepbuffsize(b, size);
+ int i;
+ buff[islittle ? 0 : size - 1] = (char)(n & MC); /* first byte */
+ for (i = 1; i < size; i++) {
+ n >>= NB;
+ buff[islittle ? i : size - 1 - i] = (char)(n & MC);
+ }
+ if (neg && size > SZINT) { /* negative number need sign extension? */
+ for (i = SZINT; i < size; i++) /* correct extra bytes */
+ buff[islittle ? i : size - 1 - i] = (char)MC;
+ }
+ luaL_addsize(b, size); /* add result to buffer */
+}
+
+
+/*
+** Copy 'size' bytes from 'src' to 'dest', correcting endianness if
+** given 'islittle' is different from native endianness.
+*/
+static void copywithendian (volatile char *dest, volatile const char *src,
+ int size, int islittle) {
+ if (islittle == nativeendian.little) {
+ while (size-- != 0)
+ *(dest++) = *(src++);
+ }
+ else {
+ dest += size - 1;
+ while (size-- != 0)
+ *(dest--) = *(src++);
+ }
+}
+
+
+static int str_pack (lua_State *L) {
+ luaL_Buffer b;
+ Header h;
+ const char *fmt = luaL_checkstring(L, 1); /* format string */
+ int arg = 1; /* current argument to pack */
+ size_t totalsize = 0; /* accumulate total size of result */
+ initheader(L, &h);
+ lua_pushnil(L); /* mark to separate arguments from string buffer */
+ luaL_buffinit(L, &b);
+ while (*fmt != '\0') {
+ int size, ntoalign;
+ KOption opt = getdetails(&h, totalsize, &fmt, &size, &ntoalign);
+ totalsize += ntoalign + size;
+ while (ntoalign-- > 0)
+ luaL_addchar(&b, LUAL_PACKPADBYTE); /* fill alignment */
+ arg++;
+ switch (opt) {
+ case Kint: { /* signed integers */
+ lua_Integer n = luaL_checkinteger(L, arg);
+ if (size < SZINT) { /* need overflow check? */
+ lua_Integer lim = (lua_Integer)1 << ((size * NB) - 1);
+ luaL_argcheck(L, -lim <= n && n < lim, arg, "integer overflow");
+ }
+ packint(&b, (lua_Unsigned)n, h.islittle, size, (n < 0));
+ break;
+ }
+ case Kuint: { /* unsigned integers */
+ lua_Integer n = luaL_checkinteger(L, arg);
+ if (size < SZINT) /* need overflow check? */
+ luaL_argcheck(L, (lua_Unsigned)n < ((lua_Unsigned)1 << (size * NB)),
+ arg, "unsigned overflow");
+ packint(&b, (lua_Unsigned)n, h.islittle, size, 0);
+ break;
+ }
+ case Kfloat: { /* floating-point options */
+ volatile Ftypes u;
+ char *buff = luaL_prepbuffsize(&b, size);
+ lua_Number n = luaL_checknumber(L, arg); /* get argument */
+ if (size == sizeof(u.f)) u.f = (float)n; /* copy it into 'u' */
+ else if (size == sizeof(u.d)) u.d = (double)n;
+ else u.n = n;
+ /* move 'u' to final result, correcting endianness if needed */
+ copywithendian(buff, u.buff, size, h.islittle);
+ luaL_addsize(&b, size);
+ break;
+ }
+ case Kchar: { /* fixed-size string */
+ size_t len;
+ const char *s = luaL_checklstring(L, arg, &len);
+ luaL_argcheck(L, len <= (size_t)size, arg,
+ "string longer than given size");
+ luaL_addlstring(&b, s, len); /* add string */
+ while (len++ < (size_t)size) /* pad extra space */
+ luaL_addchar(&b, LUAL_PACKPADBYTE);
+ break;
+ }
+ case Kstring: { /* strings with length count */
+ size_t len;
+ const char *s = luaL_checklstring(L, arg, &len);
+ luaL_argcheck(L, size >= (int)sizeof(size_t) ||
+ len < ((size_t)1 << (size * NB)),
+ arg, "string length does not fit in given size");
+ packint(&b, (lua_Unsigned)len, h.islittle, size, 0); /* pack length */
+ luaL_addlstring(&b, s, len);
+ totalsize += len;
+ break;
+ }
+ case Kzstr: { /* zero-terminated string */
+ size_t len;
+ const char *s = luaL_checklstring(L, arg, &len);
+ luaL_argcheck(L, strlen(s) == len, arg, "string contains zeros");
+ luaL_addlstring(&b, s, len);
+ luaL_addchar(&b, '\0'); /* add zero at the end */
+ totalsize += len + 1;
+ break;
+ }
+ case Kpadding: luaL_addchar(&b, LUAL_PACKPADBYTE); /* FALLTHROUGH */
+ case Kpaddalign: case Knop:
+ arg--; /* undo increment */
+ break;
+ }
+ }
+ luaL_pushresult(&b);
+ return 1;
+}
+
+
+static int str_packsize (lua_State *L) {
+ Header h;
+ const char *fmt = luaL_checkstring(L, 1); /* format string */
+ size_t totalsize = 0; /* accumulate total size of result */
+ initheader(L, &h);
+ while (*fmt != '\0') {
+ int size, ntoalign;
+ KOption opt = getdetails(&h, totalsize, &fmt, &size, &ntoalign);
+ size += ntoalign; /* total space used by option */
+ luaL_argcheck(L, totalsize <= MAXSIZE - size, 1,
+ "format result too large");
+ totalsize += size;
+ switch (opt) {
+ case Kstring: /* strings with length count */
+ case Kzstr: /* zero-terminated string */
+ luaL_argerror(L, 1, "variable-length format");
+ /* call never return, but to avoid warnings: *//* FALLTHROUGH */
+ default: break;
+ }
+ }
+ lua_pushinteger(L, (lua_Integer)totalsize);
+ return 1;
+}
+
+
+/*
+** Unpack an integer with 'size' bytes and 'islittle' endianness.
+** If size is smaller than the size of a Lua integer and integer
+** is signed, must do sign extension (propagating the sign to the
+** higher bits); if size is larger than the size of a Lua integer,
+** it must check the unread bytes to see whether they do not cause an
+** overflow.
+*/
+static lua_Integer unpackint (lua_State *L, const char *str,
+ int islittle, int size, int issigned) {
+ lua_Unsigned res = 0;
+ int i;
+ int limit = (size <= SZINT) ? size : SZINT;
+ for (i = limit - 1; i >= 0; i--) {
+ res <<= NB;
+ res |= (lua_Unsigned)(unsigned char)str[islittle ? i : size - 1 - i];
+ }
+ if (size < SZINT) { /* real size smaller than lua_Integer? */
+ if (issigned) { /* needs sign extension? */
+ lua_Unsigned mask = (lua_Unsigned)1 << (size*NB - 1);
+ res = ((res ^ mask) - mask); /* do sign extension */
+ }
+ }
+ else if (size > SZINT) { /* must check unread bytes */
+ int mask = (!issigned || (lua_Integer)res >= 0) ? 0 : MC;
+ for (i = limit; i < size; i++) {
+ if ((unsigned char)str[islittle ? i : size - 1 - i] != mask)
+ luaL_error(L, "%d-byte integer does not fit into Lua Integer", size);
+ }
+ }
+ return (lua_Integer)res;
+}
+
+
+static int str_unpack (lua_State *L) {
+ Header h;
+ const char *fmt = luaL_checkstring(L, 1);
+ size_t ld;
+ const char *data = luaL_checklstring(L, 2, &ld);
+ size_t pos = (size_t)posrelat(luaL_optinteger(L, 3, 1), ld) - 1;
+ int n = 0; /* number of results */
+ luaL_argcheck(L, pos <= ld, 3, "initial position out of string");
+ initheader(L, &h);
+ while (*fmt != '\0') {
+ int size, ntoalign;
+ KOption opt = getdetails(&h, pos, &fmt, &size, &ntoalign);
+ if ((size_t)ntoalign + size > ~pos || pos + ntoalign + size > ld)
+ luaL_argerror(L, 2, "data string too short");
+ pos += ntoalign; /* skip alignment */
+ /* stack space for item + next position */
+ luaL_checkstack(L, 2, "too many results");
+ n++;
+ switch (opt) {
+ case Kint:
+ case Kuint: {
+ lua_Integer res = unpackint(L, data + pos, h.islittle, size,
+ (opt == Kint));
+ lua_pushinteger(L, res);
+ break;
+ }
+ case Kfloat: {
+ volatile Ftypes u;
+ lua_Number num;
+ copywithendian(u.buff, data + pos, size, h.islittle);
+ if (size == sizeof(u.f)) num = (lua_Number)u.f;
+ else if (size == sizeof(u.d)) num = (lua_Number)u.d;
+ else num = u.n;
+ lua_pushnumber(L, num);
+ break;
+ }
+ case Kchar: {
+ lua_pushlstring(L, data + pos, size);
+ break;
+ }
+ case Kstring: {
+ size_t len = (size_t)unpackint(L, data + pos, h.islittle, size, 0);
+ luaL_argcheck(L, pos + len + size <= ld, 2, "data string too short");
+ lua_pushlstring(L, data + pos + size, len);
+ pos += len; /* skip string */
+ break;
+ }
+ case Kzstr: {
+ size_t len = (int)strlen(data + pos);
+ lua_pushlstring(L, data + pos, len);
+ pos += len + 1; /* skip string plus final '\0' */
+ break;
+ }
+ case Kpaddalign: case Kpadding: case Knop:
+ n--; /* undo increment */
+ break;
+ }
+ pos += size;
+ }
+ lua_pushinteger(L, pos + 1); /* next position */
+ return n + 1;
+}
+
+/* }====================================================== */
+
+
+static const luaL_Reg strlib[] = {
+ {"byte", str_byte},
+ {"char", str_char},
+ {"dump", str_dump},
+ {"find", str_find},
+ {"format", str_format},
+ {"gmatch", gmatch},
+ {"gsub", str_gsub},
+ {"len", str_len},
+ {"lower", str_lower},
+ {"match", str_match},
+ {"rep", str_rep},
+ {"reverse", str_reverse},
+ {"sub", str_sub},
+ {"upper", str_upper},
+ {"pack", str_pack},
+ {"packsize", str_packsize},
+ {"unpack", str_unpack},
+ {NULL, NULL}
+};
+
+
+static void createmetatable (lua_State *L) {
+ lua_createtable(L, 0, 1); /* table to be metatable for strings */
+ lua_pushliteral(L, ""); /* dummy string */
+ lua_pushvalue(L, -2); /* copy table */
+ lua_setmetatable(L, -2); /* set table as metatable for strings */
+ lua_pop(L, 1); /* pop dummy string */
+ lua_pushvalue(L, -2); /* get string library */
+ lua_setfield(L, -2, "__index"); /* metatable.__index = string */
+ lua_pop(L, 1); /* pop metatable */
+}
+
+
+/*
+** Open string library
+*/
+LUAMOD_API int luaopen_string (lua_State *L) {
+ luaL_newlib(L, strlib);
+ createmetatable(L);
+ return 1;
+}
+