commit 82d09fbf0dbd5aee890f033b25b09dc48ce58a48
parent 9be85d164855e74140b9da0c55568d7b7bf49d8a
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 15 Dec 1997 15:58:28 -0200
new structure for closures, without static variables.
Diffstat:
| M | lstrlib.c | | | 112 | ++++++++++++++++++++++++++++++++++++++++++++----------------------------------- |
1 file changed, 62 insertions(+), 50 deletions(-)
diff --git a/lstrlib.c b/lstrlib.c
@@ -1,5 +1,5 @@
/*
-** $Id: lstrlib.c,v 1.2 1997/11/26 18:53:45 roberto Exp roberto $
+** $Id: lstrlib.c,v 1.3 1997/12/09 13:35:19 roberto Exp roberto $
** Standard library for strings and pattern-matching
** See Copyright Notice in lua.h
*/
@@ -145,45 +145,47 @@ static void str_ascii (void)
#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 */
+struct Capture {
+ struct {
+ char *init;
+ int len; /* -1 signals unfinished capture */
+ } capture[MAX_CAPT];
+ int level; /* total number of captures (finished or unfinished) */
+};
#define ESC '%'
#define SPECIALS "^$*?.([%-"
-static void push_captures (void)
+static void push_captures (struct Capture *cap)
{
int i;
- for (i=0; i<num_captures; i++) {
- int l = capture[i].len;
+ for (i=0; i<cap->level; i++) {
+ int l = cap->capture[i].len;
char *buff = openspace(l+1);
if (l == -1) lua_error("unfinished capture");
- strncpy(buff, capture[i].init, l);
+ strncpy(buff, cap->capture[i].init, l);
buff[l] = 0;
lua_pushstring(buff);
}
}
-static int check_cap (int l, int level)
+static int check_cap (int l, struct Capture *cap)
{
l -= '1';
- if (!(0 <= l && l < level && capture[l].len != -1))
+ if (!(0 <= l && l < cap->level && cap->capture[l].len != -1))
lua_error("invalid capture index");
return l;
}
-static int capture_to_close (int level)
+static int capture_to_close (struct Capture *cap)
{
+ int level = cap->level;
for (level--; level>=0; level--)
- if (capture[level].len == -1) return level;
+ if (cap->capture[level].len == -1) return level;
lua_error("invalid pattern capture");
return 0; /* to avoid warnings */
}
@@ -269,15 +271,15 @@ static char *matchbalance (char *s, int b, int e)
}
-static char *matchitem (char *s, char *p, int level, char **ep)
+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, level);
+ int l = check_cap(*p, cap);
*ep = p+1;
- if (strncmp(capture[l].init, s, capture[l].len) == 0)
- return s+capture[l].len;
+ if (strncmp(cap->capture[l].init, s, cap->capture[l].len) == 0)
+ return s+cap->capture[l].len;
else return NULL;
}
else if (*p == 'b') { /* balanced string */
@@ -293,58 +295,61 @@ static char *matchitem (char *s, char *p, int level, char **ep)
}
-static char *match (char *s, char *p, int level)
+static char *match (char *s, char *p, struct Capture *cap)
{
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 '(': { /* 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(level);
+ int l = capture_to_close(cap);
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 */
+ 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 == 0)) {
- num_captures = level;
+ if (*p == 0 || (*(p+1) == 0 && *s == 0))
return s;
- }
/* else go through */
default: { /* it is a pattern item */
char *ep; /* get what is next */
- char *s1 = matchitem(s, p, level, &ep);
+ char *s1 = matchitem(s, p, cap, &ep);
switch (*ep) {
case '*': { /* repetition */
char *res;
- if (s1 && (res = match(s1, p, level)))
+ if (s1 && (res = match(s1, p, cap)))
return res;
- p=ep+1; goto init; /* else return match(s, ep+1, level); */
+ p=ep+1; goto init; /* else return match(s, ep+1, cap); */
}
case '-': { /* repetition */
char *res;
- if ((res = match(s, ep+1, level)) != 0)
+ if ((res = match(s, ep+1, cap)) != 0)
return res;
else if (s1) {
s = s1;
- goto init; /* return match(s1, p, level); */
+ goto init; /* return match(s1, p, cap); */
}
else
return NULL;
}
case '?': { /* optional */
char *res;
- if (s1 && (res = match(s1, ep+1, level)))
+ if (s1 && (res = match(s1, ep+1, cap)))
return res;
- p=ep+1; goto init; /* else return match(s, ep+1, level); */
+ p=ep+1; goto init; /* else return match(s, ep+1, cap); */
}
default:
- if (s1) { s=s1; p=ep; goto init; } /* return match(s1, ep, level); */
+ if (s1) { s=s1; p=ep; goto init; } /* return match(s1, ep, cap); */
else return NULL;
}
}
@@ -370,11 +375,13 @@ static void str_find (void)
int anchor = (*p == '^') ? (p++, 1) : 0;
char *s1=s+init;
do {
+ struct Capture cap;
char *res;
- if ((res=match(s1, p, 0)) != NULL) {
+ cap.level = 0;
+ if ((res=match(s1, p, &cap)) != NULL) {
lua_pushnumber(s1-s+1); /* start */
lua_pushnumber(res-s); /* end */
- push_captures();
+ push_captures(&cap);
return;
}
} while (*s1++ && !anchor);
@@ -382,7 +389,7 @@ static void str_find (void)
}
-static void add_s (lua_Object newp)
+static void add_s (lua_Object newp, struct Capture *cap)
{
if (lua_isstring(newp)) {
char *news = lua_getstring(newp);
@@ -390,8 +397,8 @@ static void add_s (lua_Object newp)
if (*news != ESC || !isdigit((unsigned char)*++news))
luaI_addchar(*news++);
else {
- int l = check_cap(*news++, num_captures);
- addnchar(capture[l].init, capture[l].len);
+ int l = check_cap(*news++, cap);
+ addnchar(cap->capture[l].init, cap->capture[l].len);
}
}
}
@@ -400,7 +407,7 @@ static void add_s (lua_Object newp)
struct lbuff oldbuff;
int status;
lua_beginblock();
- push_captures();
+ push_captures(cap);
/* function may use lbuffer, so save it and create a luaM_new one */
oldbuff = lbuffer;
lbuffer.b = NULL; lbuffer.max = lbuffer.size = 0;
@@ -428,10 +435,13 @@ static void str_gsub (void)
int n = 0;
luaI_emptybuff();
while (n < max_s) {
- char *e = match(src, p, 0);
+ struct Capture cap;
+ char *e;
+ cap.level = 0;
+ e = match(src, p, &cap);
if (e) {
n++;
- add_s(newp);
+ add_s(newp, &cap);
}
if (e && e>src) /* non empty match? */
src = e; /* skip it */
@@ -471,11 +481,13 @@ static void str_format (void)
luaI_addchar(*strfrmt++); /* %% */
else { /* format item */
char form[MAX_FORMAT]; /* store the format ('%...') */
+ struct Capture cap;
char *buff;
char *initf = strfrmt;
form[0] = '%';
- strfrmt = match(strfrmt, "%d?%$?[-+ #]*(%d*)%.?(%d*)", 0);
- if (capture[0].len > 3 || capture[1].len > 3) /* < 1000? */
+ cap.level = 0;
+ strfrmt = match(strfrmt, "%d?%$?[-+ #]*(%d*)%.?(%d*)", &cap);
+ if (cap.capture[0].len > 3 || cap.capture[1].len > 3) /* < 1000? */
lua_error("invalid format (width or precision too long)");
if (isdigit((unsigned char)initf[0]) && initf[1] == '$') {
arg = initf[0] - '0';
