commit 1630c2533a99e808ecf4649b637f45c964b1c477
parent 1d373d77de72ee8baacf69ba53e9e61af6b9caa3
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Thu, 1 Aug 1996 11:55:13 -0300
Pattern-Matching!
plus several other changes...
Diffstat:
| M | strlib.c | | | 494 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++---------------------- |
1 file changed, 359 insertions(+), 135 deletions(-)
diff --git a/strlib.c b/strlib.c
@@ -3,42 +3,68 @@
** String library to LUA
*/
-char *rcs_strlib="$Id: strlib.c,v 1.23 1996/04/30 21:13:55 roberto Exp roberto $";
+char *rcs_strlib="$Id: strlib.c,v 1.24 1996/05/22 21:59:07 roberto Exp roberto $";
#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
-#include <limits.h>
#include "lua.h"
#include "lualib.h"
-void lua_arg_error(char *funcname)
+static char *buffer = NULL;
+static size_t maxbuff = 0;
+static size_t buff_size = 0;
+
+
+static char *lua_strbuffer (unsigned long size)
+{
+ if (size > maxbuff) {
+ buffer = (buffer) ? realloc(buffer, maxbuff=size) : malloc(maxbuff=size);
+ if (buffer == NULL)
+ lua_error("memory overflow");
+ }
+ return buffer;
+}
+
+static char *openspace (unsigned long size)
{
- char buff[100];
- sprintf(buff, "incorrect arguments to function `%s'", funcname);
- lua_error(buff);
+ char *buff = lua_strbuffer(buff_size+size);
+ return buff+buff_size;
+}
+
+void lua_arg_check(int cond, char *funcname)
+{
+ if (!cond) {
+ char buff[100];
+ sprintf(buff, "incorrect argument to function `%s'", funcname);
+ lua_error(buff);
+ }
}
char *lua_check_string (int numArg, char *funcname)
{
lua_Object o = lua_getparam(numArg);
- if (!lua_isstring(o))
- lua_arg_error(funcname);
+ lua_arg_check(lua_isstring(o), funcname);
return lua_getstring(o);
}
+char *lua_opt_string (int numArg, char *def, char *funcname)
+{
+ return (lua_getparam(numArg) == LUA_NOOBJECT) ? def :
+ lua_check_string(numArg, funcname);
+}
+
double lua_check_number (int numArg, char *funcname)
{
lua_Object o = lua_getparam(numArg);
- if (!lua_isnumber(o))
- lua_arg_error(funcname);
+ lua_arg_check(lua_isnumber(o), funcname);
return lua_getnumber(o);
}
-static long lua_opt_number (int numArg, long def, char *funcname)
+long lua_opt_number (int numArg, long def, char *funcname)
{
return (lua_getparam(numArg) == LUA_NOOBJECT) ? def :
(long)lua_check_number(numArg, funcname);
@@ -46,54 +72,45 @@ static long lua_opt_number (int numArg, long def, char *funcname)
char *luaI_addchar (int c)
{
- static char *buff = NULL;
- static size_t max = 0;
- static size_t n = 0;
- if (n >= max)
- {
- if (max == 0)
- {
- max = 100;
- buff = (char *)malloc(max);
- }
- else
- {
- max *= 2;
- buff = (char *)realloc(buff, max);
- }
- if (buff == NULL)
- lua_error("memory overflow");
- }
- buff[n++] = c;
+ if (buff_size >= maxbuff)
+ lua_strbuffer(maxbuff == 0 ? 100 : maxbuff*2);
+ buffer[buff_size++] = c;
if (c == 0)
- n = 0; /* prepare for next string */
- return buff;
+ buff_size = 0; /* prepare for next string */
+ return buffer;
+}
+
+static void addnchar (char *s, int n)
+{
+ char *b = openspace(n);
+ strncpy(b, s, n);
+ buff_size += n;
}
/*
-** Return the position of the first caracter of a substring into a string
-** LUA interface:
-** n = strfind (string, substring, init, end)
+** Interface to strtok
*/
-static void str_find (void)
+static void str_tok (void)
{
- char *s1 = lua_check_string(1, "strfind");
- char *s2 = lua_check_string(2, "strfind");
- long init = lua_opt_number(3, 1, "strfind") - 1;
- char *f = (init>=0 && init<=strlen(s1)) ? strstr(s1+init,s2) : NULL;
- if (f != NULL)
- {
- size_t pos = f-s1+1;
- if (lua_opt_number(4, LONG_MAX, "strfind") >= pos+strlen(s2)-1)
- lua_pushnumber (pos);
- else
- lua_pushnil();
- }
- else
- lua_pushnil();
+ char *s1 = lua_check_string(1, "strtok");
+ char *del = lua_check_string(2, "strtok");
+ lua_Object t = lua_createtable();
+ int i = 1;
+ /* As strtok changes s1, and s1 is "constant", make a copy of it */
+ s1 = strcpy(lua_strbuffer(strlen(s1+1)), s1);
+ while ((s1 = strtok(s1, del)) != NULL) {
+ lua_pushobject(t);
+ lua_pushnumber(i++);
+ lua_pushstring(s1);
+ lua_storesubscript();
+ s1 = NULL; /* prepare for next strtok */
+ }
+ lua_pushobject(t);
+ lua_pushnumber(i-1); /* total number of tokens */
}
+
/*
** Return the string length
** LUA interface:
@@ -101,11 +118,9 @@ static void str_find (void)
*/
static void str_len (void)
{
- char *s = lua_check_string(1, "strlen");
- lua_pushnumber(strlen(s));
+ lua_pushnumber(strlen(lua_check_string(1, "strlen")));
}
-
/*
** Return the substring of a string, from start to end
** LUA interface:
@@ -113,136 +128,342 @@ static void str_len (void)
*/
static void str_sub (void)
{
- char *s = lua_check_string(1, "strsub");
- long start = (long)lua_check_number(2, "strsub");
- long end = lua_opt_number(3, strlen(s), "strsub");
- if (end < start || start < 1 || end > strlen(s))
- lua_pushliteral("");
- else
- {
- luaI_addchar(0);
- while (start <= end)
- luaI_addchar(s[start++ - 1]);
- lua_pushstring (luaI_addchar(0));
- }
+ char *s = lua_check_string(1, "strsub");
+ long start = (long)lua_check_number(2, "strsub");
+ long end = lua_opt_number(3, strlen(s), "strsub");
+ if (1 <= start && start <= end && end <= strlen(s)) {
+ luaI_addchar(0);
+ addnchar(s+start-1, end-start+1);
+ lua_pushstring(luaI_addchar(0));
+ }
+ else lua_pushliteral("");
}
/*
-** Convert a string to lower case.
-** LUA interface:
-** lowercase = strlower (string)
+** Transliterate a string
*/
-static void str_lower (void)
+static void str_map (void)
{
- char *s = lua_check_string(1, "strlower");
- luaI_addchar(0);
- while (*s)
- luaI_addchar(tolower(*s++));
+ char *s = lua_check_string(1, "strmap");
+ char *from = lua_check_string(2, "strmap");
+ char *to = lua_opt_string(3, "", "strmap");
+ long len = strlen(to);
+ for (luaI_addchar(0); *s; s++) {
+ char *f = strrchr(from, *s);
+ if (f == NULL)
+ luaI_addchar(*s);
+ else {
+ long pos = f-from;
+ if (pos < len)
+ luaI_addchar(to[pos]);
+ }
+ }
lua_pushstring(luaI_addchar(0));
}
-
/*
-** Convert a string to upper case.
-** LUA interface:
-** uppercase = strupper (string)
+** get ascii value of a character in a string
*/
-static void str_upper (void)
+static void str_ascii (void)
+{
+ char *s = lua_check_string(1, "ascii");
+ long pos = lua_opt_number(2, 1, "ascii") - 1;
+ lua_arg_check(0<=pos && pos<strlen(s), "ascii");
+ lua_pushnumber((unsigned char)s[pos]);
+}
+
+
+/* pattern matching */
+
+#define ESC '%'
+#define SPECIALS "^$*?.([%"
+
+static char *item_end (char *p)
+{
+ switch (*p) {
+ case '\0': return p;
+ case ESC:
+ if (*(p+1) == 0) lua_error("incorrect pattern");
+ return p+2;
+ case '[': {
+ char *end = (*(p+1) == 0) ? NULL : strchr(p+2, ']');
+ if (end == NULL) lua_error("incorrect pattern");
+ return end+1;
+ }
+ default:
+ return 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;
+ default: return (cl == c);
+ }
+ return (islower(cl) ? res : !res);
+}
+
+static int singlematch (int c, char *p)
+{
+ if (c == 0) return 0;
+ switch (*p) {
+ case '.': return 1;
+ case ESC: return matchclass(c, *(p+1));
+ case '[': {
+ char *end = strchr(p+2, ']');
+ int sig = *(p+1) == '^' ? (p++, 0) : 1;
+ while (++p < end) {
+ if (*p == ESC) {
+ if (((p+1) < end) && matchclass(c, *++p)) return sig;
+ }
+ else if ((*(p+1) == '-') && (p+2 < end)) {
+ p+=2;
+ if (*(p-2) <= c && c <= *p) return sig;
+ }
+ else if (*p == c) return sig;
+ }
+ return !sig;
+ }
+ default: return (*p == c);
+ }
+}
+
+#define MAX_CAPT 9
+
+static struct {
+ char *init;
+ int len; /* -1 signals unfinished capture */
+} capture[MAX_CAPT];
+
+static int num_captures; /* only valid after a sucessful call to match */
+
+
+static void push_captures (void)
{
- char *s = lua_check_string(1, "strupper");
+ int i;
luaI_addchar(0);
- while (*s)
- luaI_addchar(toupper(*s++));
+ for (i=0; i<num_captures; i++) {
+ if (capture[i].len == -1) lua_error("unfinished capture");
+ addnchar(capture[i].init, capture[i].len);
+ lua_pushstring(luaI_addchar(0));
+ }
+}
+
+static int check_cap (int l, int level)
+{
+ l -= '1';
+ if (!(0 <= l && l < level && capture[l].len != -1))
+ lua_error("invalid capture index");
+ return l;
+}
+
+static void add_s (char *newp)
+{
+ while (*newp) {
+ if (*newp != ESC || !isdigit(*++newp))
+ luaI_addchar(*newp++);
+ else {
+ int l = check_cap(*newp++, num_captures);
+ addnchar(capture[l].init, capture[l].len);
+ }
+ }
+}
+
+static int capture_to_close (int level)
+{
+ for (level--; level>=0; level--)
+ if (capture[level].len == -1) return level;
+ lua_error("invalid pattern capture");
+ return 0; /* to avoid warnings */
+}
+
+static char *match (char *s, char *p, int level)
+{
+ init: /* using goto's to optimize tail recursion */
+ switch (*p) {
+ case '(': /* start capture */
+ if (level >= MAX_CAPT) lua_error("too many captures");
+ capture[level].init = s;
+ capture[level].len = -1;
+ level++; p++; goto init; /* return match(s, p+1, level); */
+ case ')': { /* end capture */
+ int l = capture_to_close(level);
+ char *res;
+ capture[l].len = s - capture[l].init; /* close capture */
+ if ((res = match(s, p+1, level)) == NULL) /* match failed? */
+ capture[l].len = -1; /* undo capture */
+ return res;
+ }
+ case ESC: /* possibly a capture (if followed by a digit) */
+ if (!isdigit(*(p+1))) goto dflt;
+ else {
+ int l = check_cap(*(p+1), level);
+ if (strncmp(capture[l].init, s, capture[l].len) == 0) {
+ /* return match(p+2, s+capture[l].len, level); */
+ p+=2; s+=capture[l].len; goto init;
+ }
+ else return NULL;
+ }
+ case '\0': case '$': /* (possibly) end of pattern */
+ if (*p == 0 || (*(p+1) == 0 && *s == 0)) {
+ num_captures = level;
+ return s;
+ }
+ else goto dflt;
+ default: dflt: { /* it is a pattern item */
+ int m = singlematch(*s, p);
+ char *ep = item_end(p); /* get what is next */
+ switch (*ep) {
+ case '*': { /* repetition? */
+ char *res;
+ if (m && (res = match(s+1, p, level)))
+ return res;
+ p=ep+1; goto init; /* else return match(s, ep+1, level); */
+ }
+ case '?': { /* optional? */
+ char *res;
+ if (m && (res = match(s+1, ep+1, level)))
+ return res;
+ p=ep+1; goto init; /* else return match(s, ep+1, level); */
+ }
+ default:
+ if (m) { s++; p=ep; goto init; } /* return match(s+1, ep, level); */
+ else return NULL;
+ }
+ }
+ }
+}
+
+static void str_find (void)
+{
+ char *s = lua_check_string(1, "find");
+ char *p = lua_check_string(2, "find");
+ long init = lua_opt_number(3, 1, "strfind") - 1;
+ lua_arg_check(0 <= init && init <= strlen(s), "find");
+ if (strpbrk(p, SPECIALS) == NULL) { /* no special caracters? */
+ char *s2 = strstr(s+init, p);
+ if (s2) {
+ lua_pushnumber(s2-s+1);
+ lua_pushnumber(s2-s+strlen(p));
+ }
+ }
+ else {
+ int anchor = (*p == '^') ? (p++, 1) : 0;
+ char *s1=s+init;
+ do {
+ char *res;
+ if ((res=match(s1, p, 0)) != NULL) {
+ lua_pushnumber(s1-s+1); /* start */
+ lua_pushnumber(res-s); /* end */
+ push_captures();
+ return;
+ }
+ } while (*s1++ && !anchor);
+ }
+}
+
+static void str_s (void)
+{
+ char *src = lua_check_string(1, "s");
+ char *p = lua_check_string(2, "s");
+ char *newp = lua_check_string(3, "s");
+ int max_s = lua_opt_number(4, strlen(src), "s");
+ int anchor = (*p == '^') ? (p++, 1) : 0;
+ int n = 0;
+ luaI_addchar(0);
+ while (*src && n < max_s) {
+ char *e;
+ if ((e=match(src, p, 0)) == NULL)
+ luaI_addchar(*src++);
+ else {
+ if (e == src) lua_error("empty pattern in substitution"); /* ??? */
+ add_s(newp);
+ src = e;
+ n++;
+ }
+ if (anchor) break;
+ }
+ addnchar(src, strlen(src));
lua_pushstring(luaI_addchar(0));
+ lua_pushnumber(n); /* number of substitutions */
}
-/*
-** get ascii value of a character in a string
-*/
-static void str_ascii (void)
+static void str_set (void)
{
- char *s = lua_check_string(1, "ascii");
- long pos = lua_opt_number(2, 1, "ascii") - 1;
- if (pos<0 || pos>=strlen(s))
- lua_arg_error("ascii");
- lua_pushnumber(s[pos]);
+ char *item = lua_check_string(1, "strset");
+ int i;
+ lua_arg_check(*item_end(item) == 0, "strset");
+ luaI_addchar(0);
+ for (i=1; i<256; i++) /* 0 cannot be part of a set */
+ if (singlematch(i, item))
+ luaI_addchar(i);
+ lua_pushstring(luaI_addchar(0));
}
+
void luaI_addquoted (char *s)
{
luaI_addchar('"');
- for (; *s; s++)
- {
- if (*s == '"' || *s == '\\' || *s == '\n')
+ for (; *s; s++) {
+ if (strchr("\"\\\n", *s))
luaI_addchar('\\');
luaI_addchar(*s);
}
luaI_addchar('"');
}
-#define MAX_CONVERTION 2000
-#define MAX_FORMAT 50
+#define MAX_FORMAT 200
static void str_format (void)
{
int arg = 1;
char *strfrmt = lua_check_string(arg++, "format");
luaI_addchar(0); /* initialize */
- while (*strfrmt)
- {
+ while (*strfrmt) {
if (*strfrmt != '%')
luaI_addchar(*strfrmt++);
else if (*++strfrmt == '%')
luaI_addchar(*strfrmt++); /* %% */
- else
- { /* format item */
+ else { /* format item */
char form[MAX_FORMAT]; /* store the format ('%...') */
- char buff[MAX_CONVERTION]; /* store the formated value */
- int size = 0;
- int i = 0;
- form[i++] = '%';
- form[i] = *strfrmt++;
- while (!isalpha(form[i]))
- {
- if (isdigit(form[i]))
- {
- size = size*10 + form[i]-'0';
- if (size >= MAX_CONVERTION)
- lua_error("format size/precision too long in function `format'");
- }
- else if (form[i] == '.')
- size = 0; /* re-start */
- if (++i >= MAX_FORMAT)
- lua_error("bad format in function `format'");
- form[i] = *strfrmt++;
- }
- form[i+1] = 0; /* ends string */
- switch (form[i])
- {
+ char *buff;
+ char *initf = strfrmt-1; /* -1 to include % */
+ strfrmt = match(strfrmt, "[-+ #]*(%d*)%.?(%d*)", 0);
+ if (capture[0].len > 3 || capture[1].len > 3) /* < 1000? */
+ lua_error("invalid format (width/precision too long)");
+ strncpy(form, initf, strfrmt-initf+1); /* +1 to include convertion */
+ form[strfrmt-initf+1] = 0;
+ buff = openspace(1000); /* to store the formated value */
+ switch (*strfrmt++) {
case 'q':
luaI_addquoted(lua_check_string(arg++, "format"));
- buff[0] = '\0'; /* addchar already done */
break;
- case 's':
- {
+ case 's': {
char *s = lua_check_string(arg++, "format");
- if (strlen(s) >= MAX_CONVERTION)
- lua_error("string argument too long in function `format'");
- sprintf(buff, form, s);
+ buff = openspace(strlen(s));
+ buff_size += sprintf(buff, form, s);
break;
}
case 'c': case 'd': case 'i': case 'o':
case 'u': case 'x': case 'X':
- sprintf(buff, form, (int)lua_check_number(arg++, "format"));
+ buff_size += sprintf(buff, form,
+ (int)lua_check_number(arg++, "format"));
break;
case 'e': case 'E': case 'f': case 'g':
- sprintf(buff, form, lua_check_number(arg++, "format"));
+ buff_size += sprintf(buff, form, lua_check_number(arg++, "format"));
break;
default: /* also treat cases 'pnLlh' */
lua_error("invalid format option in function `format'");
}
- for (i=0; buff[i]; i++) /* move formated value to result */
- luaI_addchar(buff[i]);
}
}
lua_pushstring(luaI_addchar(0)); /* push the result */
@@ -256,14 +477,17 @@ void luaI_openlib (struct lua_reg *l, int n)
lua_register(l[i].name, l[i].func);
}
+
static struct lua_reg strlib[] = {
-{"strfind", str_find},
+{"strtok", str_tok},
{"strlen", str_len},
{"strsub", str_sub},
-{"strlower", str_lower},
-{"strupper", str_upper},
+{"strset", str_set},
+{"strmap", str_map},
{"ascii", str_ascii},
-{"format", str_format}
+{"format", str_format},
+{"strfind", str_find},
+{"s", str_s}
};
