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authorLua Team <team@lua.org>1998-07-11 12:00:00 +0000
committerrepogen <>1998-07-11 12:00:00 +0000
commit377347776f1f3d820f92151f70bec667f96d5e6b (patch)
treecdb3ba26158df33547dfe765547177afcee119d1 /src/lib/lstrlib.c
parent4f8c5d0f284e1f4da717aea5008915f185cd2e05 (diff)
downloadlua-github-3.1.tar.gz
Lua 3.13.1
Diffstat (limited to 'src/lib/lstrlib.c')
-rw-r--r--src/lib/lstrlib.c541
1 files changed, 541 insertions, 0 deletions
diff --git a/src/lib/lstrlib.c b/src/lib/lstrlib.c
new file mode 100644
index 00000000..dc79cc7e
--- /dev/null
+++ b/src/lib/lstrlib.c
@@ -0,0 +1,541 @@
+/*
+** $Id: lstrlib.c,v 1.18 1998/07/01 14:21:57 roberto Exp $
+** Standard library for strings and pattern-matching
+** See Copyright Notice in lua.h
+*/
+
+
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lauxlib.h"
+#include "lua.h"
+#include "lualib.h"
+
+
+
+static void addnchar (char *s, int n)
+{
+ char *b = luaL_openspace(n);
+ memcpy(b, s, n);
+ luaL_addsize(n);
+}
+
+
+static void str_len (void)
+{
+ long l;
+ luaL_check_lstr(1, &l);
+ lua_pushnumber(l);
+}
+
+
+static void closeandpush (void)
+{
+ lua_pushlstring(luaL_buffer(), luaL_getsize());
+}
+
+
+static long posrelat (long pos, long len)
+{
+ /* relative string position: negative means back from end */
+ return (pos>=0) ? pos : len+pos+1;
+}
+
+
+static void str_sub (void)
+{
+ long l;
+ char *s = luaL_check_lstr(1, &l);
+ long start = posrelat(luaL_check_number(2), l);
+ long end = posrelat(luaL_opt_number(3, -1), l);
+ if (1 <= start && start <= end && end <= l)
+ lua_pushlstring(s+start-1, end-start+1);
+ else lua_pushstring("");
+}
+
+
+static void str_lower (void)
+{
+ long l;
+ int i;
+ char *s = luaL_check_lstr(1, &l);
+ luaL_resetbuffer();
+ for (i=0; i<l; i++)
+ luaL_addchar(tolower((unsigned char)(s[i])));
+ closeandpush();
+}
+
+
+static void str_upper (void)
+{
+ long l;
+ int i;
+ char *s = luaL_check_lstr(1, &l);
+ luaL_resetbuffer();
+ for (i=0; i<l; i++)
+ luaL_addchar(toupper((unsigned char)(s[i])));
+ closeandpush();
+}
+
+static void str_rep (void)
+{
+ long l;
+ char *s = luaL_check_lstr(1, &l);
+ int n = (int)luaL_check_number(2);
+ luaL_resetbuffer();
+ while (n-- > 0)
+ addnchar(s, l);
+ closeandpush();
+}
+
+
+static void str_byte (void)
+{
+ long l;
+ char *s = luaL_check_lstr(1, &l);
+ long pos = posrelat(luaL_opt_number(2, 1), l);
+ luaL_arg_check(0<pos && pos<=l, 2, "out of range");
+ lua_pushnumber((unsigned char)s[pos-1]);
+}
+
+static void str_char (void) {
+ int i = 0;
+ luaL_resetbuffer();
+ while (lua_getparam(++i) != LUA_NOOBJECT) {
+ double c = luaL_check_number(i);
+ luaL_arg_check((unsigned char)c == c, i, "invalid value");
+ luaL_addchar((int)c);
+ }
+ closeandpush();
+}
+
+
+/*
+** =======================================================
+** PATTERN MATCHING
+** =======================================================
+*/
+
+#define MAX_CAPT 9
+
+struct Capture {
+ int level; /* total number of captures (finished or unfinished) */
+ char *src_end; /* end ('\0') of source string */
+ struct {
+ char *init;
+ int len; /* -1 signals unfinished capture */
+ } capture[MAX_CAPT];
+};
+
+
+#define ESC '%'
+#define SPECIALS "^$*?.([%-"
+
+
+static void push_captures (struct Capture *cap)
+{
+ int i;
+ for (i=0; i<cap->level; i++)
+ lua_pushlstring(cap->capture[i].init, cap->capture[i].len);
+}
+
+
+static int check_cap (int l, struct Capture *cap)
+{
+ l -= '1';
+ if (!(0 <= l && l < cap->level && cap->capture[l].len != -1))
+ lua_error("invalid capture index");
+ return l;
+}
+
+
+static int capture_to_close (struct Capture *cap)
+{
+ int level = cap->level;
+ for (level--; level>=0; level--)
+ if (cap->capture[level].len == -1) return level;
+ lua_error("invalid pattern capture");
+ return 0; /* to avoid warnings */
+}
+
+
+static char *bracket_end (char *p)
+{
+ return (*p == 0) ? NULL : strchr((*p=='^') ? p+2 : p+1, ']');
+}
+
+
+static int matchclass (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 '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 'z' : res = (c == '\0'); break;
+ default: return (cl == c);
+ }
+ return (islower((unsigned char)cl) ? res : !res);
+}
+
+
+int luaI_singlematch (int c, char *p, char **ep)
+{
+ switch (*p) {
+ case '.': /* matches any char */
+ *ep = p+1;
+ return 1;
+ case '\0': /* end of pattern; matches nothing */
+ *ep = p;
+ return 0;
+ case ESC:
+ if (*(++p) == '\0')
+ luaL_verror("incorrect pattern (ends with `%c')", ESC);
+ *ep = p+1;
+ return matchclass(c, (unsigned char)*p);
+ case '[': {
+ char *end = bracket_end(p+1);
+ int sig = *(p+1) == '^' ? (p++, 0) : 1;
+ if (end == NULL) lua_error("incorrect pattern (missing `]')");
+ *ep = end+1;
+ while (++p < end) {
+ if (*p == ESC) {
+ if (((p+1) < end) && matchclass(c, (unsigned char)*++p))
+ return sig;
+ }
+ else if ((*(p+1) == '-') && (p+2 < end)) {
+ p+=2;
+ if ((unsigned char)*(p-2) <= c && c <= (unsigned char)*p)
+ return sig;
+ }
+ else if ((unsigned char)*p == c) return sig;
+ }
+ return !sig;
+ }
+ default:
+ *ep = p+1;
+ return ((unsigned char)*p == c);
+ }
+}
+
+
+static char *matchbalance (char *s, int b, int e, struct Capture *cap)
+{
+ if (*s != b) return NULL;
+ else {
+ int cont = 1;
+ while (++s < cap->src_end) {
+ if (*s == e) {
+ if (--cont == 0) return s+1;
+ }
+ else if (*s == b) cont++;
+ }
+ }
+ return NULL; /* string ends out of balance */
+}
+
+
+static char *matchitem (char *s, char *p, struct Capture *cap, char **ep)
+{
+ if (*p == ESC) {
+ p++;
+ if (isdigit((unsigned char)*p)) { /* capture */
+ int l = check_cap(*p, cap);
+ int len = cap->capture[l].len;
+ *ep = p+1;
+ if (cap->src_end-s >= len && memcmp(cap->capture[l].init, s, len) == 0)
+ return s+len;
+ else return NULL;
+ }
+ else if (*p == 'b') { /* balanced string */
+ p++;
+ if (*p == 0 || *(p+1) == 0)
+ lua_error("unbalanced pattern");
+ *ep = p+2;
+ return matchbalance(s, *p, *(p+1), cap);
+ }
+ else p--; /* and go through */
+ }
+ /* "luaI_singlematch" sets "ep" (so must be called even when *s == 0) */
+ return (luaI_singlematch((unsigned char)*s, p, ep) && s<cap->src_end) ?
+ s+1 : NULL;
+}
+
+
+static char *match (char *s, char *p, struct Capture *cap)
+{
+ init: /* using goto's to optimize tail recursion */
+ switch (*p) {
+ case '(': { /* start capture */
+ char *res;
+ if (cap->level >= MAX_CAPT) lua_error("too many captures");
+ cap->capture[cap->level].init = s;
+ cap->capture[cap->level].len = -1;
+ cap->level++;
+ if ((res=match(s, p+1, cap)) == NULL) /* match failed? */
+ cap->level--; /* undo capture */
+ return res;
+ }
+ case ')': { /* end capture */
+ int l = capture_to_close(cap);
+ char *res;
+ cap->capture[l].len = s - cap->capture[l].init; /* close capture */
+ if ((res = match(s, p+1, cap)) == NULL) /* match failed? */
+ cap->capture[l].len = -1; /* undo capture */
+ return res;
+ }
+ case '\0': case '$': /* (possibly) end of pattern */
+ if (*p == 0 || (*(p+1) == 0 && s == cap->src_end))
+ return s;
+ /* else go through */
+ default: { /* it is a pattern item */
+ char *ep; /* get what is next */
+ char *s1 = matchitem(s, p, cap, &ep);
+ switch (*ep) {
+ case '*': { /* repetition */
+ char *res;
+ if (s1 && s1>s && ((res=match(s1, p, cap)) != NULL))
+ return res;
+ p=ep+1; goto init; /* else return match(s, ep+1, cap); */
+ }
+ case '?': { /* optional */
+ char *res;
+ if (s1 && ((res=match(s1, ep+1, cap)) != NULL))
+ return res;
+ p=ep+1; goto init; /* else return match(s, ep+1, cap); */
+ }
+ case '-': { /* repetition */
+ char *res;
+ if ((res = match(s, ep+1, cap)) != NULL)
+ return res;
+ else if (s1 && s1>s) {
+ s = s1;
+ goto init; /* return match(s1, p, cap); */
+ }
+ else
+ return NULL;
+ }
+ default:
+ if (s1) { s=s1; p=ep; goto init; } /* return match(s1, ep, cap); */
+ else return NULL;
+ }
+ }
+ }
+}
+
+
+static void str_find (void)
+{
+ long l;
+ char *s = luaL_check_lstr(1, &l);
+ char *p = luaL_check_string(2);
+ long init = posrelat(luaL_opt_number(3, 1), l) - 1;
+ struct Capture cap;
+ luaL_arg_check(0 <= init && init <= l, 3, "out of range");
+ if (lua_getparam(4) != LUA_NOOBJECT ||
+ strpbrk(p, SPECIALS) == NULL) { /* no special characters? */
+ char *s2 = strstr(s+init, p);
+ if (s2) {
+ lua_pushnumber(s2-s+1);
+ lua_pushnumber(s2-s+strlen(p));
+ return;
+ }
+ }
+ else {
+ int anchor = (*p == '^') ? (p++, 1) : 0;
+ char *s1=s+init;
+ cap.src_end = s+l;
+ do {
+ char *res;
+ cap.level = 0;
+ if ((res=match(s1, p, &cap)) != NULL) {
+ lua_pushnumber(s1-s+1); /* start */
+ lua_pushnumber(res-s); /* end */
+ push_captures(&cap);
+ return;
+ }
+ } while (s1++<cap.src_end && !anchor);
+ }
+ lua_pushnil(); /* if arrives here, it didn't find */
+}
+
+
+static void add_s (lua_Object newp, struct Capture *cap)
+{
+ if (lua_isstring(newp)) {
+ char *news = lua_getstring(newp);
+ int l = lua_strlen(newp);
+ int i;
+ for (i=0; i<l; i++) {
+ if (news[i] != ESC)
+ luaL_addchar(news[i]);
+ else {
+ i++; /* skip ESC */
+ if (!isdigit((unsigned char)news[i]))
+ luaL_addchar(news[i]);
+ else {
+ int level = check_cap(news[i], cap);
+ addnchar(cap->capture[level].init, cap->capture[level].len);
+ }
+ }
+ }
+ }
+ else { /* is a function */
+ lua_Object res;
+ int status;
+ int oldbuff;
+ lua_beginblock();
+ push_captures(cap);
+ /* function may use buffer, so save it and create a new one */
+ oldbuff = luaL_newbuffer(0);
+ status = lua_callfunction(newp);
+ /* restore old buffer */
+ luaL_oldbuffer(oldbuff);
+ if (status != 0) {
+ lua_endblock();
+ lua_error(NULL);
+ }
+ res = lua_getresult(1);
+ if (lua_isstring(res))
+ addnchar(lua_getstring(res), lua_strlen(res));
+ lua_endblock();
+ }
+}
+
+
+static void str_gsub (void)
+{
+ long srcl;
+ char *src = luaL_check_lstr(1, &srcl);
+ char *p = luaL_check_string(2);
+ lua_Object newp = lua_getparam(3);
+ int max_s = (int)luaL_opt_number(4, srcl+1);
+ int anchor = (*p == '^') ? (p++, 1) : 0;
+ int n = 0;
+ struct Capture cap;
+ luaL_arg_check(lua_isstring(newp) || lua_isfunction(newp), 3,
+ "string or function expected");
+ luaL_resetbuffer();
+ cap.src_end = src+srcl;
+ while (n < max_s) {
+ char *e;
+ cap.level = 0;
+ e = match(src, p, &cap);
+ if (e) {
+ n++;
+ add_s(newp, &cap);
+ }
+ if (e && e>src) /* non empty match? */
+ src = e; /* skip it */
+ else if (src < cap.src_end)
+ luaL_addchar(*src++);
+ else break;
+ if (anchor) break;
+ }
+ addnchar(src, cap.src_end-src);
+ closeandpush();
+ lua_pushnumber(n); /* number of substitutions */
+}
+
+
+static void luaI_addquoted (char *s)
+{
+ luaL_addchar('"');
+ for (; *s; s++) {
+ if (strchr("\"\\\n", *s))
+ luaL_addchar('\\');
+ luaL_addchar(*s);
+ }
+ luaL_addchar('"');
+}
+
+#define MAX_FORMAT 200
+
+static void str_format (void)
+{
+ int arg = 1;
+ char *strfrmt = luaL_check_string(arg);
+ struct Capture cap;
+ cap.src_end = strfrmt+strlen(strfrmt)+1;
+ luaL_resetbuffer();
+ while (*strfrmt) {
+ if (*strfrmt != '%')
+ luaL_addchar(*strfrmt++);
+ else if (*++strfrmt == '%')
+ luaL_addchar(*strfrmt++); /* %% */
+ else { /* format item */
+ char form[MAX_FORMAT]; /* store the format ('%...') */
+ char *buff;
+ char *initf = strfrmt;
+ form[0] = '%';
+ cap.level = 0;
+ if (isdigit((unsigned char)initf[0]) && initf[1] == '$') {
+ arg = initf[0] - '0';
+ initf += 2; /* skip the 'n$' */
+ }
+ arg++;
+ strfrmt = match(initf, "[-+ #0]*(%d*)%.?(%d*)", &cap);
+ if (cap.capture[0].len > 2 || cap.capture[1].len > 2) /* < 100? */
+ lua_error("invalid format (width or precision too long)");
+ strncpy(form+1, initf, strfrmt-initf+1); /* +1 to include conversion */
+ form[strfrmt-initf+2] = 0;
+ buff = luaL_openspace(1000); /* to store the formatted value */
+ switch (*strfrmt++) {
+ case 'q':
+ luaI_addquoted(luaL_check_string(arg));
+ continue;
+ case 's': {
+ char *s = luaL_check_string(arg);
+ buff = luaL_openspace(strlen(s));
+ sprintf(buff, form, s);
+ break;
+ }
+ case 'c': case 'd': case 'i':
+ sprintf(buff, form, (int)luaL_check_number(arg));
+ break;
+ case 'o': case 'u': case 'x': case 'X':
+ sprintf(buff, form, (unsigned int)luaL_check_number(arg));
+ break;
+ case 'e': case 'E': case 'f': case 'g': case 'G':
+ sprintf(buff, form, luaL_check_number(arg));
+ break;
+ default: /* also treat cases 'pnLlh' */
+ lua_error("invalid option in `format'");
+ }
+ luaL_addsize(strlen(buff));
+ }
+ }
+ closeandpush(); /* push the result */
+}
+
+
+static struct luaL_reg strlib[] = {
+{"strlen", str_len},
+{"strsub", str_sub},
+{"strlower", str_lower},
+{"strupper", str_upper},
+{"strchar", str_char},
+{"strrep", str_rep},
+{"ascii", str_byte}, /* for compatibility */
+{"strbyte", str_byte},
+{"format", str_format},
+{"strfind", str_find},
+{"gsub", str_gsub}
+};
+
+
+/*
+** Open string library
+*/
+void strlib_open (void)
+{
+ luaL_openlib(strlib, (sizeof(strlib)/sizeof(strlib[0])));
+}