0,0 → 1,969 |
/* |
** $Id: lstrlib.c,v 1.173 2011/11/30 18:24:56 roberto Exp $ |
** Standard library for string operations and pattern-matching |
** See Copyright Notice in lua.h |
*/ |
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#include <ctype.h> |
#include <stddef.h> |
#include <stdio.h> |
#include <stdlib.h> |
#include <string.h> |
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#define lstrlib_c |
#define LUA_LIB |
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#include "lua.h" |
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#include "lauxlib.h" |
#include "lualib.h" |
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/* |
** maximum number of captures that a pattern can do during |
** pattern-matching. This limit is arbitrary. |
*/ |
#if !defined(LUA_MAXCAPTURES) |
#define LUA_MAXCAPTURES 32 |
#endif |
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/* macro to `unsign' a character */ |
#define uchar(c) ((unsigned char)(c)) |
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static int str_len (lua_State *L) { |
size_t l; |
luaL_checklstring(L, 1, &l); |
lua_pushinteger(L, (lua_Integer)l); |
return 1; |
} |
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/* translate a relative string position: negative means back from end */ |
static size_t posrelat (ptrdiff_t pos, size_t len) { |
if (pos >= 0) return (size_t)pos; |
else if (0u - (size_t)pos > len) return 0; |
else return len - ((size_t)-pos) + 1; |
} |
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static int str_sub (lua_State *L) { |
size_t l; |
const char *s = luaL_checklstring(L, 1, &l); |
size_t start = posrelat(luaL_checkinteger(L, 2), l); |
size_t end = posrelat(luaL_optinteger(L, 3, -1), l); |
if (start < 1) start = 1; |
if (end > l) end = l; |
if (start <= end) |
lua_pushlstring(L, s + start - 1, end - start + 1); |
else lua_pushliteral(L, ""); |
return 1; |
} |
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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; |
} |
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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; |
} |
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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; |
} |
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/* reasonable limit to avoid arithmetic overflow */ |
#define MAXSIZE ((~(size_t)0) >> 1) |
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static int str_rep (lua_State *L) { |
size_t l, lsep; |
const char *s = luaL_checklstring(L, 1, &l); |
int n = luaL_checkint(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 = n * l + (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; |
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; |
} |
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static int str_byte (lua_State *L) { |
size_t l; |
const char *s = luaL_checklstring(L, 1, &l); |
size_t posi = posrelat(luaL_optinteger(L, 2, 1), l); |
size_t pose = posrelat(luaL_optinteger(L, 3, posi), l); |
int n, i; |
if (posi < 1) posi = 1; |
if (pose > l) pose = l; |
if (posi > pose) return 0; /* empty interval; return no values */ |
n = (int)(pose - posi + 1); |
if (posi + n <= pose) /* (size_t -> int) overflow? */ |
return luaL_error(L, "string slice too long"); |
luaL_checkstack(L, n, "string slice too long"); |
for (i=0; i<n; i++) |
lua_pushinteger(L, uchar(s[posi+i-1])); |
return n; |
} |
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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++) { |
int c = luaL_checkint(L, i); |
luaL_argcheck(L, uchar(c) == c, i, "value out of range"); |
p[i - 1] = uchar(c); |
} |
luaL_pushresultsize(&b, n); |
return 1; |
} |
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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; |
} |
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static int str_dump (lua_State *L) { |
luaL_Buffer b; |
luaL_checktype(L, 1, LUA_TFUNCTION); |
lua_settop(L, 1); |
luaL_buffinit(L,&b); |
if (lua_dump(L, writer, &b) != 0) |
return luaL_error(L, "unable to dump given function"); |
luaL_pushresult(&b); |
return 1; |
} |
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/* |
** {====================================================== |
** PATTERN MATCHING |
** ======================================================= |
*/ |
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#define CAP_UNFINISHED (-1) |
#define CAP_POSITION (-2) |
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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 level; /* total number of captures (finished or unfinished) */ |
struct { |
const char *init; |
ptrdiff_t len; |
} capture[LUA_MAXCAPTURES]; |
} MatchState; |
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#define L_ESC '%' |
#define SPECIALS "^$*+?.([%-" |
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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; |
} |
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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"); |
} |
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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 " LUA_QL("%%") ")"); |
return p+1; |
} |
case '[': { |
if (*p == '^') p++; |
do { /* look for a `]' */ |
if (p == ms->p_end) |
luaL_error(ms->L, "malformed pattern (missing " LUA_QL("]") ")"); |
if (*(p++) == L_ESC && p < ms->p_end) |
p++; /* skip escapes (e.g. `%]') */ |
} while (*p != ']'); |
return p+1; |
} |
default: { |
return p; |
} |
} |
} |
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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); |
} |
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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; |
} |
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static int singlematch (int c, const char *p, const char *ep) { |
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); |
} |
} |
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static const char *match (MatchState *ms, const char *s, const char *p); |
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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 " LUA_QL("%%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 */ |
} |
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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 ((s+i)<ms->src_end && singlematch(uchar(*(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; |
} |
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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 (s<ms->src_end && singlematch(uchar(*s), p, ep)) |
s++; /* try with one more repetition */ |
else return NULL; |
} |
} |
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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; |
} |
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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; |
} |
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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; |
} |
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static const char *match (MatchState *ms, const char *s, const char *p) { |
init: /* using goto's to optimize tail recursion */ |
if (p == ms->p_end) /* end of pattern? */ |
return s; /* match succeeded */ |
switch (*p) { |
case '(': { /* start capture */ |
if (*(p+1) == ')') /* position capture? */ |
return start_capture(ms, s, p+2, CAP_POSITION); |
else |
return start_capture(ms, s, p+1, CAP_UNFINISHED); |
} |
case ')': { /* end capture */ |
return end_capture(ms, s, p+1); |
} |
case '$': { |
if ((p+1) == ms->p_end) /* is the `$' the last char in pattern? */ |
return (s == ms->src_end) ? s : NULL; /* check end of string */ |
else goto dflt; |
} |
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) return NULL; |
p+=4; goto init; /* else return match(ms, s, p+4); */ |
} |
case 'f': { /* frontier? */ |
const char *ep; char previous; |
p += 2; |
if (*p != '[') |
luaL_error(ms->L, "missing " LUA_QL("[") " after " |
LUA_QL("%%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)) return NULL; |
p=ep; goto init; /* else return match(ms, s, ep); */ |
} |
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) return NULL; |
p+=2; goto init; /* else return match(ms, s, p+2) */ |
} |
default: goto dflt; |
} |
} |
default: dflt: { /* pattern class plus optional suffix */ |
const char *ep = classend(ms, p); /* points to what is next */ |
int m = s < ms->src_end && singlematch(uchar(*s), p, ep); |
switch (*ep) { |
case '?': { /* optional */ |
const char *res; |
if (m && ((res=match(ms, s+1, ep+1)) != NULL)) |
return res; |
p=ep+1; goto init; /* else return match(ms, s, ep+1); */ |
} |
case '*': { /* 0 or more repetitions */ |
return max_expand(ms, s, p, ep); |
} |
case '+': { /* 1 or more repetitions */ |
return (m ? max_expand(ms, s+1, p, ep) : NULL); |
} |
case '-': { /* 0 or more repetitions (minimum) */ |
return min_expand(ms, s, p, ep); |
} |
default: { |
if (!m) return NULL; |
s++; p=ep; goto init; /* else return match(ms, s+1, ep); */ |
} |
} |
} |
} |
} |
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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 */ |
} |
} |
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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"); |
} |
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); |
} |
} |
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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 */ |
} |
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/* 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 */ |
} |
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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); |
size_t init = posrelat(luaL_optinteger(L, 3, 1), ls); |
if (init < 1) init = 1; |
else if (init > 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 - 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 */ |
} |
ms.L = L; |
ms.src_init = s; |
ms.src_end = s + ls; |
ms.p_end = p + lp; |
do { |
const char *res; |
ms.level = 0; |
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; |
} |
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static int str_find (lua_State *L) { |
return str_find_aux(L, 1); |
} |
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static int str_match (lua_State *L) { |
return str_find_aux(L, 0); |
} |
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static int gmatch_aux (lua_State *L) { |
MatchState ms; |
size_t ls, lp; |
const char *s = lua_tolstring(L, lua_upvalueindex(1), &ls); |
const char *p = lua_tolstring(L, lua_upvalueindex(2), &lp); |
const char *src; |
ms.L = L; |
ms.src_init = s; |
ms.src_end = s+ls; |
ms.p_end = p + lp; |
for (src = s + (size_t)lua_tointeger(L, lua_upvalueindex(3)); |
src <= ms.src_end; |
src++) { |
const char *e; |
ms.level = 0; |
if ((e = match(&ms, src, p)) != NULL) { |
lua_Integer newstart = e-s; |
if (e == src) newstart++; /* empty match? go at least one position */ |
lua_pushinteger(L, newstart); |
lua_replace(L, lua_upvalueindex(3)); |
return push_captures(&ms, src, e); |
} |
} |
return 0; /* not found */ |
} |
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static int gmatch (lua_State *L) { |
luaL_checkstring(L, 1); |
luaL_checkstring(L, 2); |
lua_settop(L, 2); |
lua_pushinteger(L, 0); |
lua_pushcclosure(L, gmatch_aux, 3); |
return 1; |
} |
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static void add_s (MatchState *ms, luaL_Buffer *b, const char *s, |
const char *e) { |
size_t l, i; |
const char *news = lua_tolstring(ms->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(ms->L, "invalid use of " LUA_QL("%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_addvalue(b); /* add capture to accumulated result */ |
} |
} |
} |
} |
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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 */ |
} |
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static int str_gsub (lua_State *L) { |
size_t srcl, lp; |
const char *src = luaL_checklstring(L, 1, &srcl); |
const char *p = luaL_checklstring(L, 2, &lp); |
int tr = lua_type(L, 3); |
size_t max_s = luaL_optinteger(L, 4, srcl+1); |
int anchor = (*p == '^'); |
size_t n = 0; |
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 */ |
} |
ms.L = L; |
ms.src_init = src; |
ms.src_end = src+srcl; |
ms.p_end = p + lp; |
while (n < max_s) { |
const char *e; |
ms.level = 0; |
e = match(&ms, src, p); |
if (e) { |
n++; |
add_value(&ms, &b, src, e, tr); |
} |
if (e && e>src) /* non empty match? */ |
src = e; /* skip it */ |
else if (src < ms.src_end) |
luaL_addchar(&b, *src++); |
else break; |
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 |
** ======================================================= |
*/ |
|
/* |
** LUA_INTFRMLEN is the length modifier for integer conversions in |
** 'string.format'; LUA_INTFRM_T is the integer type corresponding to |
** the previous length |
*/ |
#if !defined(LUA_INTFRMLEN) /* { */ |
#if defined(LUA_USE_LONGLONG) |
|
#define LUA_INTFRMLEN "ll" |
#define LUA_INTFRM_T long long |
|
#else |
|
#define LUA_INTFRMLEN "l" |
#define LUA_INTFRM_T long |
|
#endif |
#endif /* } */ |
|
#define MAX_UINTFRM ((lua_Number)(~(unsigned LUA_INTFRM_T)0)) |
#define MAX_INTFRM ((lua_Number)((~(unsigned LUA_INTFRM_T)0)/2)) |
#define MIN_INTFRM (-(lua_Number)((~(unsigned LUA_INTFRM_T)0)/2) - 1) |
|
/* |
** LUA_FLTFRMLEN is the length modifier for float conversions in |
** 'string.format'; LUA_FLTFRM_T is the float type corresponding to |
** the previous length |
*/ |
#if !defined(LUA_FLTFRMLEN) |
|
#define LUA_FLTFRMLEN "" |
#define LUA_FLTFRM_T double |
|
#endif |
|
|
/* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */ |
#define MAX_ITEM 512 |
/* valid flags in a format specification */ |
#define FLAGS "-+ #0" |
/* |
** maximum size of each format specification (such as '%-099.99d') |
** (+10 accounts for %99.99x plus margin of error) |
*/ |
#define MAX_FORMAT (sizeof(FLAGS) + sizeof(LUA_INTFRMLEN) + 10) |
|
|
static void addquoted (lua_State *L, luaL_Buffer *b, int arg) { |
size_t l; |
const char *s = luaL_checklstring(L, arg, &l); |
luaL_addchar(b, '"'); |
while (l--) { |
if (*s == '"' || *s == '\\' || *s == '\n') { |
luaL_addchar(b, '\\'); |
luaL_addchar(b, *s); |
} |
else if (*s == '\0' || iscntrl(uchar(*s))) { |
char buff[10]; |
if (!isdigit(uchar(*(s+1)))) |
sprintf(buff, "\\%d", (int)uchar(*s)); |
else |
sprintf(buff, "\\%03d", (int)uchar(*s)); |
luaL_addstring(b, buff); |
} |
else |
luaL_addchar(b, *s); |
s++; |
} |
luaL_addchar(b, '"'); |
} |
|
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 = sprintf(buff, form, luaL_checkint(L, arg)); |
break; |
} |
case 'd': case 'i': { |
lua_Number n = luaL_checknumber(L, arg); |
luaL_argcheck(L, (MIN_INTFRM - 1) < n && n < (MAX_INTFRM + 1), arg, |
"not a number in proper range"); |
addlenmod(form, LUA_INTFRMLEN); |
nb = sprintf(buff, form, (LUA_INTFRM_T)n); |
break; |
} |
case 'o': case 'u': case 'x': case 'X': { |
lua_Number n = luaL_checknumber(L, arg); |
luaL_argcheck(L, 0 <= n && n < (MAX_UINTFRM + 1), arg, |
"not a non-negative number in proper range"); |
addlenmod(form, LUA_INTFRMLEN); |
nb = sprintf(buff, form, (unsigned LUA_INTFRM_T)n); |
break; |
} |
case 'e': case 'E': case 'f': |
#if defined(LUA_USE_AFORMAT) |
case 'a': case 'A': |
#endif |
case 'g': case 'G': { |
addlenmod(form, LUA_FLTFRMLEN); |
nb = sprintf(buff, form, (LUA_FLTFRM_T)luaL_checknumber(L, arg)); |
break; |
} |
case 'q': { |
addquoted(L, &b, arg); |
break; |
} |
case 's': { |
size_t l; |
const char *s = luaL_tolstring(L, arg, &l); |
if (!strchr(form, '.') && l >= 100) { |
/* no precision and string is too long to be formatted; |
keep original string */ |
luaL_addvalue(&b); |
break; |
} |
else { |
nb = sprintf(buff, form, s); |
lua_pop(L, 1); /* remove result from 'luaL_tolstring' */ |
break; |
} |
} |
default: { /* also treat cases `pnLlh' */ |
return luaL_error(L, "invalid option " LUA_QL("%%%c") " to " |
LUA_QL("format"), *(strfrmt - 1)); |
} |
} |
luaL_addsize(&b, nb); |
} |
} |
luaL_pushresult(&b); |
return 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}, |
{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; |
} |
|