diff options
Diffstat (limited to '3rdparty/lua/src/lstrlib.c')
-rw-r--r-- | 3rdparty/lua/src/lstrlib.c | 637 |
1 files changed, 524 insertions, 113 deletions
diff --git a/3rdparty/lua/src/lstrlib.c b/3rdparty/lua/src/lstrlib.c index 9261fd220db..a650b768d57 100644 --- a/3rdparty/lua/src/lstrlib.c +++ b/3rdparty/lua/src/lstrlib.c @@ -1,19 +1,22 @@ /* -** $Id: lstrlib.c,v 1.178.1.1 2013/04/12 18:48:47 roberto Exp $ +** $Id: lstrlib.c,v 1.221 2014/12/11 14:03:07 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 <limits.h> #include <stddef.h> #include <stdio.h> #include <stdlib.h> #include <string.h> -#define lstrlib_c -#define LUA_LIB - #include "lua.h" #include "lauxlib.h" @@ -29,10 +32,19 @@ #endif -/* macro to `unsign' a character */ +/* 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 MAXSIZE \ + (sizeof(size_t) < sizeof(int) ? (~(size_t)0) : (size_t)(INT_MAX)) + + + static int str_len (lua_State *L) { size_t l; @@ -43,22 +55,22 @@ static int str_len (lua_State *L) { /* 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; +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 len - ((size_t)-pos) + 1; + 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); - size_t start = posrelat(luaL_checkinteger(L, 2), l); - size_t end = posrelat(luaL_optinteger(L, 3, -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 > l) end = l; + if (end > (lua_Integer)l) end = l; if (start <= end) - lua_pushlstring(L, s + start - 1, end - start + 1); + lua_pushlstring(L, s + start - 1, (size_t)(end - start + 1)); else lua_pushliteral(L, ""); return 1; } @@ -102,25 +114,23 @@ static int str_upper (lua_State *L) { } -/* reasonable limit to avoid arithmetic overflow */ -#define MAXSIZE ((~(size_t)0) >> 1) - 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); + 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? */ + 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; + 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) { /* avoid empty 'memcpy' (may be expensive) */ - memcpy(p, sep, lsep * sizeof(char)); p += lsep; + 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) */ @@ -133,14 +143,14 @@ static int str_rep (lua_State *L) { 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); + 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 > l) pose = l; + if (pose > (lua_Integer)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? */ + if (posi + n <= pose) /* arithmetic overflow? */ return luaL_error(L, "string slice too long"); luaL_checkstack(L, n, "string slice too long"); for (i=0; i<n; i++) @@ -155,7 +165,7 @@ static int str_char (lua_State *L) { luaL_Buffer b; char *p = luaL_buffinitsize(L, &b, n); for (i=1; i<=n; i++) { - int c = luaL_checkint(L, i); + lua_Integer c = luaL_checkinteger(L, i); luaL_argcheck(L, uchar(c) == c, i, "value out of range"); p[i - 1] = uchar(c); } @@ -164,19 +174,20 @@ static int str_char (lua_State *L) { } -static int writer (lua_State *L, const void* b, size_t size, void* B) { +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); + 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) != 0) + if (lua_dump(L, writer, &b, strip) != 0) return luaL_error(L, "unable to dump given function"); luaL_pushresult(&b); return 1; @@ -243,16 +254,16 @@ 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("%%") ")"); + luaL_error(ms->L, "malformed pattern (ends with '%%')"); return p+1; } case '[': { if (*p == '^') p++; - do { /* look for a `]' */ + do { /* look for a ']' */ if (p == ms->p_end) - luaL_error(ms->L, "malformed pattern (missing " LUA_QL("]") ")"); + luaL_error(ms->L, "malformed pattern (missing ']')"); if (*(p++) == L_ESC && p < ms->p_end) - p++; /* skip escapes (e.g. `%]') */ + p++; /* skip escapes (e.g. '%]') */ } while (*p != ']'); return p+1; } @@ -287,7 +298,7 @@ static int matchbracketclass (int c, const char *p, const char *ec) { int sig = 1; if (*(p+1) == '^') { sig = 0; - p++; /* skip the `^' */ + p++; /* skip the '^' */ } while (++p < ec) { if (*p == L_ESC) { @@ -325,8 +336,7 @@ static int singlematch (MatchState *ms, const char *s, const char *p, 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") ")"); + luaL_error(ms->L, "malformed pattern (missing arguments to '%%b')"); if (*s != *p) return NULL; else { int b = *p; @@ -425,7 +435,7 @@ static const char *match (MatchState *ms, const char *s, const char *p) { break; } case '$': { - if ((p + 1) != ms->p_end) /* is the `$' the last char in pattern? */ + 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; @@ -443,8 +453,7 @@ static const char *match (MatchState *ms, const char *s, const char *p) { const char *ep; char previous; p += 2; if (*p != '[') - luaL_error(ms->L, "missing " LUA_QL("[") " after " - LUA_QL("%%f") " in pattern"); + 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) && @@ -514,16 +523,16 @@ static const char *match (MatchState *ms, const char *s, const char *p) { 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 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 */ + 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 */ + else { /* correct 'l1' and 's1' to try again */ l1 -= init-s1; s1 = init; } @@ -539,7 +548,7 @@ static void push_onecapture (MatchState *ms, int i, const char *s, 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"); + luaL_error(ms->L, "invalid capture index %%%d", i + 1); } else { ptrdiff_t l = ms->capture[i].len; @@ -578,16 +587,16 @@ 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); + lua_Integer init = posrelat(luaL_optinteger(L, 3, 1), ls); if (init < 1) init = 1; - else if (init > ls + 1) { /* start after string's end? */ + 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 - init + 1, p, lp); + 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); @@ -678,7 +687,8 @@ static int gmatch (lua_State *L) { 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); + 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]); @@ -686,14 +696,15 @@ static void add_s (MatchState *ms, luaL_Buffer *b, const char *s, 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_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 */ } } @@ -737,9 +748,9 @@ static int str_gsub (lua_State *L) { 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); + lua_Integer max_s = luaL_optinteger(L, 4, srcl + 1); int anchor = (*p == '^'); - size_t n = 0; + lua_Integer n = 0; MatchState ms; luaL_Buffer b; luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING || @@ -786,48 +797,17 @@ static int str_gsub (lua_State *L) { ** ======================================================= */ -/* -** 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 /* } */ - - -/* -** 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) +** maximum size of each format specification (such as "%-099.99d") +** (+2 for length modifiers; +10 accounts for %99.99x plus margin of error) */ -#define MAX_FORMAT (sizeof(FLAGS) + sizeof(LUA_INTFRMLEN) + 10) +#define MAX_FORMAT (sizeof(FLAGS) + 2 + 10) static void addquoted (lua_State *L, luaL_Buffer *b, int arg) { @@ -903,7 +883,7 @@ static int str_format (lua_State *L) { else if (*++strfrmt == L_ESC) luaL_addchar(&b, *strfrmt++); /* %% */ else { /* format item */ - char form[MAX_FORMAT]; /* to store the format (`%...') */ + 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) @@ -911,36 +891,23 @@ static int str_format (lua_State *L) { 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); - LUA_INTFRM_T ni = (LUA_INTFRM_T)n; - lua_Number diff = n - (lua_Number)ni; - luaL_argcheck(L, -1 < diff && diff < 1, arg, - "not a number in proper range"); - addlenmod(form, LUA_INTFRMLEN); - nb = sprintf(buff, form, ni); + nb = sprintf(buff, form, (int)luaL_checkinteger(L, arg)); break; } + case 'd': case 'i': case 'o': case 'u': case 'x': case 'X': { - lua_Number n = luaL_checknumber(L, arg); - unsigned LUA_INTFRM_T ni = (unsigned LUA_INTFRM_T)n; - lua_Number diff = n - (lua_Number)ni; - luaL_argcheck(L, -1 < diff && diff < 1, arg, - "not a non-negative number in proper range"); - addlenmod(form, LUA_INTFRMLEN); - nb = sprintf(buff, form, ni); + lua_Integer n = luaL_checkinteger(L, arg); + addlenmod(form, LUA_INTEGER_FRMLEN); + nb = sprintf(buff, form, n); break; } - case 'e': case 'E': case 'f': #if defined(LUA_USE_AFORMAT) case 'a': case 'A': #endif + case 'e': case 'E': case 'f': case 'g': case 'G': { - addlenmod(form, LUA_FLTFRMLEN); - nb = sprintf(buff, form, (LUA_FLTFRM_T)luaL_checknumber(L, arg)); + addlenmod(form, LUA_NUMBER_FRMLEN); + nb = sprintf(buff, form, luaL_checknumber(L, arg)); break; } case 'q': { @@ -962,9 +929,9 @@ static int str_format (lua_State *L) { break; } } - default: { /* also treat cases `pnLlh' */ - return luaL_error(L, "invalid option " LUA_QL("%%%c") " to " - LUA_QL("format"), *(strfrmt - 1)); + default: { /* also treat cases 'pnLlh' */ + return luaL_error(L, "invalid option '%%%c' to 'format'", + *(strfrmt - 1)); } } luaL_addsize(&b, nb); @@ -977,6 +944,447 @@ static int str_format (lua_State *L) { /* }====================================================== */ +/* +** {====================================================== +** PACK/UNPACK +** ======================================================= +*/ + + +/* value used for padding */ +#if !defined(LUA_PACKPADBYTE) +#define LUA_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) + 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, LUA_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, "wrong length"); + luaL_addlstring(&b, s, size); + 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, LUA_PACKPADBYTE); /* go through */ + 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"); + break; + 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}, @@ -992,6 +1400,9 @@ static const luaL_Reg strlib[] = { {"reverse", str_reverse}, {"sub", str_sub}, {"upper", str_upper}, + {"pack", str_pack}, + {"packsize", str_packsize}, + {"unpack", str_unpack}, {NULL, NULL} }; |