Lua 3.23.2

1 files changed, 230 insertions, 177 deletions

diff --git a/src/lib/lstrlib.c b/src/lib/lstrlib.c
index dc79cc7e..b47e21d3 100644
--- a/src/lib/lstrlib.c
+++ b/src/lib/lstrlib.c
@@ -1,5 +1,5 @@
 /*
-** $Id: lstrlib.c,v 1.18 1998/07/01 14:21:57 roberto Exp $
+** $Id: lstrlib.c,v 1.32 1999/06/17 17:04:03 roberto Exp $
 ** Standard library for strings and pattern-matching
 ** See Copyright Notice in lua.h
 */
@@ -32,33 +32,31 @@ static void str_len (void)
 }
 
 
-static void closeandpush (void)
-{
+static void closeandpush (void) {
   lua_pushlstring(luaL_buffer(), luaL_getsize());
 }
 
 
-static long posrelat (long pos, long len)
-{
+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)
-{
+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)
+  long start = posrelat(luaL_check_long(2), l);
+  long end = posrelat(luaL_opt_long(3, -1), l);
+  if (start < 1) start = 1;
+  if (end > l) end = l;
+  if (start <= end)
     lua_pushlstring(s+start-1, end-start+1);
   else lua_pushstring("");
 }
 
 
-static void str_lower (void)
-{
+static void str_lower (void) {
   long l;
   int i;
   char *s = luaL_check_lstr(1, &l);
@@ -69,8 +67,7 @@ static void str_lower (void)
 }
 
 
-static void str_upper (void)
-{
+static void str_upper (void) {
   long l;
   int i;
   char *s = luaL_check_lstr(1, &l);
@@ -84,7 +81,7 @@ static void str_rep (void)
 {
   long l;
   char *s = luaL_check_lstr(1, &l);
-  int n = (int)luaL_check_number(2);
+  int n = luaL_check_int(2);
   luaL_resetbuffer();
   while (n-- > 0)
     addnchar(s, l);
@@ -92,38 +89,42 @@ static void str_rep (void)
 }
 
 
-static void str_byte (void)
-{
+static void str_byte (void) {
   long l;
   char *s = luaL_check_lstr(1, &l);
-  long pos = posrelat(luaL_opt_number(2, 1), l);
+  long pos = posrelat(luaL_opt_long(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);
+    luaL_addchar((unsigned char)c);
   }
   closeandpush();
 }
 
 
+
 /*
-** =======================================================
+** {======================================================
 ** PATTERN MATCHING
 ** =======================================================
 */
 
-#define MAX_CAPT 9
+#ifndef MAX_CAPT
+#define MAX_CAPT 32  /* arbitrary limit */
+#endif
+
 
 struct Capture {
-  int level;  /* total number of captures (finished or unfinished) */
   char *src_end;  /* end ('\0') of source string */
+  int level;  /* total number of captures (finished or unfinished) */
   struct {
     char *init;
     int len;  /* -1 signals unfinished capture */
@@ -132,19 +133,20 @@ struct Capture {
 
 
 #define ESC	'%'
-#define SPECIALS  "^$*?.([%-"
+#define SPECIALS  "^$*+?.([%-"
 
 
-static void push_captures (struct Capture *cap)
-{
+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);
+  for (i=0; i<cap->level; i++) {
+    int l = cap->capture[i].len;
+    if (l == -1) lua_error("unfinished capture");
+    lua_pushlstring(cap->capture[i].init, l);
+  }
 }
 
 
-static int check_cap (int l, struct Capture *cap)
-{
+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");
@@ -152,8 +154,7 @@ static int check_cap (int l, struct Capture *cap)
 }
 
 
-static int capture_to_close (struct Capture *cap)
-{
+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;
@@ -162,14 +163,25 @@ static int capture_to_close (struct Capture *cap)
 }
 
 
-static char *bracket_end (char *p)
-{
-  return (*p == 0) ? NULL : strchr((*p=='^') ? p+2 : p+1, ']');
+char *luaI_classend (char *p) {
+  switch (*p++) {
+    case ESC:
+      if (*p == '\0')
+        luaL_verror("incorrect pattern (ends with `%c')", ESC);
+      return p+1;
+    case '[':
+      if (*p == '^') p++;
+      if (*p == ']') p++;
+      p = strchr(p, ']');
+      if (!p) lua_error("incorrect pattern (missing `]')");
+      return p+1;
+    default:
+      return p;
+  }
 }
 
 
-static int matchclass (int c, int cl)
-{
+static int matchclass (int c, int cl) {
   int res;
   switch (tolower(cl)) {
     case 'a' : res = isalpha(c); break;
@@ -180,57 +192,63 @@ static int matchclass (int c, int cl)
     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;
     default: return (cl == c);
   }
-  return (islower((unsigned char)cl) ? res : !res);
+  return (islower(cl) ? res : !res);
 }
 
 
-int luaI_singlematch (int c, char *p, char **ep)
-{
+
+static int matchbracketclass (int c, char *p, char *end) {
+  int sig = 1;
+  if (*(p+1) == '^') {
+    sig = 0;
+    p++;  /* skip the '^' */
+  }
+  while (++p < end) {
+    if (*p == ESC) {
+      p++;
+      if ((p < end) && matchclass(c, (unsigned char)*p))
+        return sig;
+    }
+    else if ((*(p+1) == '-') && (p+2 < end)) {
+      p+=2;
+      if ((int)(unsigned char)*(p-2) <= c && c <= (int)(unsigned char)*p)
+        return sig;
+    }
+    else if ((unsigned char)*p == c) return sig;
+  }
+  return !sig;
+}
+
+
+
+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;
-    }
+      return matchclass(c, (unsigned char)*(p+1));
+    case '[':
+      return matchbracketclass(c, p, ep-1);
     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;
+static char *match (char *s, char *p, struct Capture *cap);
+
+
+static char *matchbalance (char *s, char *p, struct Capture *cap) {
+  if (*p == 0 || *(p+1) == 0)
+    lua_error("unbalanced pattern");
+  if (*s != *p) return NULL;
   else {
+    int b = *p;
+    int e = *(p+1);
     int cont = 1;
     while (++s < cap->src_end) {
       if (*s == e) {
@@ -243,101 +261,120 @@ static char *matchbalance (char *s, int b, int e, struct Capture *cap)
 }
 
 
-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 */
+static char *max_expand (char *s, char *p, char *ep, struct Capture *cap) {
+  int i = 0;  /* counts maximum expand for item */
+  while ((s+i)<cap->src_end && luaI_singlematch((unsigned char)*(s+i), p, ep))
+    i++;
+  /* keeps trying to match mith the maximum repetitions */
+  while (i>=0) {
+    char *res = match((s+i), ep+1, cap);
+    if (res) return res;
+    i--;  /* else didn't match; reduce 1 repetition to try again */
   }
-  /* "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;
+  return NULL;
 }
 
 
-static char *match (char *s, char *p, struct Capture *cap)
-{
+static char *min_expand (char *s, char *p, char *ep, struct Capture *cap) {
+  for (;;) {
+    char *res = match(s, ep+1, cap);
+    if (res != NULL)
+      return res;
+    else if (s<cap->src_end && luaI_singlematch((unsigned char)*s, p, ep))
+      s++;  /* try with one more repetition */
+    else return NULL;
+  }
+}
+
+
+static char *start_capt (char *s, char *p, struct Capture *cap) {
+  char *res;
+  int level = cap->level;
+  if (level >= MAX_CAPT) lua_error("too many captures");
+  cap->capture[level].init = s;
+  cap->capture[level].len = -1;
+  cap->level = level+1;
+  if ((res=match(s, p+1, cap)) == NULL)  /* match failed? */
+    cap->level--;  /* undo capture */
+  return res;
+}
+
+
+static char *end_capt (char *s, char *p, struct Capture *cap) {
+  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;
+}
+
+
+static char *match_capture (char *s, int level, struct Capture *cap) {
+  int l = check_cap(level, cap);
+  int len = cap->capture[l].len;
+  if (cap->src_end-s >= len &&
+      memcmp(cap->capture[l].init, s, len) == 0)
+    return s+len;
+  else return 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 '$':  /* (possibly) end of pattern */
-      if (*p == 0 || (*(p+1) == 0 && s == cap->src_end))
-        return s;
-      /* else go through */
-    default: {  /* it is a pattern item */
-      char *ep;  /* get what is next */
-      char *s1 = matchitem(s, p, cap, &ep);
+    case '(':  /* start capture */
+      return start_capt(s, p, cap);
+    case ')':  /* end capture */
+      return end_capt(s, p, cap);
+    case ESC:  /* may be %[0-9] or %b */
+      if (isdigit((unsigned char)(*(p+1)))) {  /* capture? */
+        s = match_capture(s, *(p+1), cap);
+        if (s == NULL) return NULL;
+        p+=2; goto init;  /* else return match(p+2, s, cap) */
+      }
+      else if (*(p+1) == 'b') {  /* balanced string? */
+        s = matchbalance(s, p+2, cap);
+        if (s == NULL) return NULL;
+        p+=4; goto init;  /* else return match(p+4, s, cap); */
+      }
+      else goto dflt;  /* case default */
+    case '\0':  /* end of pattern */
+      return s;  /* match succeeded */
+    case '$':
+      if (*(p+1) == '\0')  /* is the '$' the last char in pattern? */
+        return (s == cap->src_end) ? s : NULL;  /* check end of string */
+      else goto dflt;
+    default: dflt: {  /* it is a pattern item */
+      char *ep = luaI_classend(p);  /* points to what is next */
+      int m = s<cap->src_end && luaI_singlematch((unsigned char)*s, p, 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))
+          if (m && ((res=match(s+1, 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;
-        }
+        case '*':  /* 0 or more repetitions */
+          return max_expand(s, p, ep, cap);
+        case '+':  /* 1 or more repetitions */
+          return (m ? max_expand(s+1, p, ep, cap) : NULL);
+        case '-':  /* 0 or more repetitions (minimum) */
+          return min_expand(s, p, ep, cap);
         default:
-          if (s1) { s=s1; p=ep; goto init; }  /* return match(s1, ep, cap); */
-          else return NULL;
+          if (!m) return NULL;
+          s++; p=ep; goto init;  /* else return match(s+1, ep, cap); */
       }
     }
   }
 }
 
 
-static void str_find (void)
-{
+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;
+  long init = posrelat(luaL_opt_long(3, 1), l) - 1;
   struct Capture cap;
   luaL_arg_check(0 <= init && init <= l, 3, "out of range");
   if (lua_getparam(4) != LUA_NOOBJECT ||
@@ -368,8 +405,7 @@ static void str_find (void)
 }
 
 
-static void add_s (lua_Object newp, struct Capture *cap)
-{
+static void add_s (lua_Object newp, struct Capture *cap) {
   if (lua_isstring(newp)) {
     char *news = lua_getstring(newp);
     int l = lua_strlen(newp);
@@ -411,13 +447,12 @@ static void add_s (lua_Object newp, struct Capture *cap)
 }
 
 
-static void str_gsub (void)
-{
+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 max_s = luaL_opt_int(4, srcl+1);
   int anchor = (*p == '^') ? (p++, 1) : 0;
   int n = 0;
   struct Capture cap;
@@ -445,26 +480,33 @@ static void str_gsub (void)
   lua_pushnumber(n);  /* number of substitutions */
 }
 
+/* }====================================================== */
 
-static void luaI_addquoted (char *s)
-{
+
+static void luaI_addquoted (int arg) {
+  long l;
+  char *s = luaL_check_lstr(arg, &l);
   luaL_addchar('"');
-  for (; *s; s++) {
-    if (strchr("\"\\\n", *s))
-      luaL_addchar('\\');
-    luaL_addchar(*s);
+  while (l--) {
+    switch (*s) {
+      case '"':  case '\\':  case '\n':
+        luaL_addchar('\\');
+        luaL_addchar(*s);
+        break;
+      case '\0': addnchar("\\000", 4); break;
+      default: luaL_addchar(*s);
+    }
+    s++;
   }
   luaL_addchar('"');
 }
 
-#define MAX_FORMAT 200
+/* maximum size of each format specification (such as '%-099.99d') */
+#define MAX_FORMAT 20  /* arbitrary limit */
 
-static void str_format (void)
-{
+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 != '%')
@@ -472,34 +514,28 @@ static void str_format (void)
     else if (*++strfrmt == '%')
       luaL_addchar(*strfrmt++);  /* %% */
     else { /* format item */
-      char form[MAX_FORMAT];      /* store the format ('%...') */
-      char *buff;
+      struct Capture cap;
+      char form[MAX_FORMAT];  /* to store the format ('%...') */
+      char *buff;  /* to store the formatted item */
       char *initf = strfrmt;
       form[0] = '%';
-      cap.level = 0;
-      if (isdigit((unsigned char)initf[0]) && initf[1] == '$') {
-        arg = initf[0] - '0';
+      if (isdigit((unsigned char)*initf) && *(initf+1) == '$') {
+        arg = *initf - '0';
         initf += 2;  /* skip the 'n$' */
       }
       arg++;
+      cap.src_end = strfrmt+strlen(strfrmt)+1;
+      cap.level = 0;
       strfrmt = match(initf, "[-+ #0]*(%d*)%.?(%d*)", &cap);
-      if (cap.capture[0].len > 2 || cap.capture[1].len > 2)  /* < 100? */
+      if (cap.capture[0].len > 2 || cap.capture[1].len > 2 ||  /* < 100? */
+          strfrmt-initf > MAX_FORMAT-2)
         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 */
+      buff = luaL_openspace(512);  /* 512 > size of format('%99.99f', -1e308) */
       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));
+          sprintf(buff, form, luaL_check_int(arg));
           break;
         case 'o':  case 'u':  case 'x':  case 'X':
           sprintf(buff, form, (unsigned int)luaL_check_number(arg));
@@ -507,6 +543,23 @@ static void str_format (void)
         case 'e':  case 'E': case 'f': case 'g': case 'G':
           sprintf(buff, form, luaL_check_number(arg));
           break;
+        case 'q':
+          luaI_addquoted(arg);
+          continue;  /* skip the "addsize" at the end */
+        case 's': {
+          long l;
+          char *s = luaL_check_lstr(arg, &l);
+          if (cap.capture[1].len == 0 && l >= 100) {
+            /* no precision and string is too big to be formatted;
+               keep original string */
+            addnchar(s, l);
+            continue;  /* skip the "addsize" at the end */
+          }
+          else {
+            sprintf(buff, form, s);
+            break;
+          }
+        }
         default:  /* also treat cases 'pnLlh' */
           lua_error("invalid option in `format'");
       }
@@ -524,7 +577,7 @@ static struct luaL_reg strlib[] = {
 {"strupper", str_upper},
 {"strchar", str_char},
 {"strrep", str_rep},
-{"ascii", str_byte},  /* for compatibility */
+{"ascii", str_byte},  /* for compatibility with 3.0 and earlier */
 {"strbyte", str_byte},
 {"format", str_format},
 {"strfind", str_find},