* dln.c (dln_find_1): backport from trunkn. [ruby-core:25802]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@25368 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 86 insertions, 64 deletions

diff --git a/dln.c b/dln.c
index 5a2f8dfcd4..aea6e1c3f1 100644
--- a/dln.c
+++ b/dln.c
@@ -1653,6 +1653,8 @@ dln_load(file)
 
 static char *dln_find_1();
 
+static char fbuf[MAXPATHLEN];
+
 char *
 dln_find_exe(fname, path)
     const char *fname;
@@ -1669,7 +1671,7 @@ dln_find_exe(fname, path)
 	path = "/usr/local/bin:/usr/ucb:/usr/bin:/bin:.";
 #endif
     }
-    return dln_find_1(fname, path, 1);
+    return dln_find_1(fname, path, fbuf, sizeof(fbuf), 1);
 }
 
 char *
@@ -1682,45 +1684,95 @@ dln_find_file(fname, path)
     return dln_find_1(fname, path, 0);
 #else
     if (!path) path = ".";
-    return _macruby_path_conv_posix_to_macos(dln_find_1(fname, path, 0));
+    return _macruby_path_conv_posix_to_macos(dln_find_1(fname, path, fbuf, sizeof(fbuf), 0));
 #endif
 }
 
-static char fbuf[MAXPATHLEN];
-
 static char *
-dln_find_1(fname, path, exe_flag)
-    const char *fname;
-    const char *path;
-    int exe_flag;		/* non 0 if looking for executable. */
+dln_find_1(const char *fname, const char *path, char *fbuf, size_t size,
+	   int exe_flag /* non 0 if looking for executable. */)
 {
     register const char *dp;
     register const char *ep;
     register char *bp;
     struct stat st;
-#ifdef __MACOS__
-    const char* mac_fullpath;
+    size_t i, fspace;
+#ifdef DOSISH
+    static const char extension[][5] = {
+	".exe", ".com", ".cmd", ".bat",
+    };
+    size_t j;
+    int is_abs = 0, has_path = 0;
+    const char *ext = 0;
+    const char *p = fname;
 #endif
 
-    if (!fname) return (char *)fname;
-    if (fname[0] == '/') return (char *)fname;
-    if (strncmp("./", fname, 2) == 0 || strncmp("../", fname, 3) == 0)
-      return (char *)fname;
-    if (exe_flag && strchr(fname, '/')) return (char *)fname;
+#define RETURN_IF(expr) if (expr) return (char *)fname;
+
+    RETURN_IF(!fname);
 #ifdef DOSISH
-    if (fname[0] == '\\') return (char *)fname;
+# ifndef CharNext
+# define CharNext(p) ((p)+1)
+# endif
 # ifdef DOSISH_DRIVE_LETTER
-    if (strlen(fname) > 2 && fname[1] == ':') return (char *)fname;
+    if (((p[0] | 0x20) - 'a') < 26  && p[1] == ':') {
+	p += 2;
+	is_abs = 1;
+    }
 # endif
-    if (strncmp(".\\", fname, 2) == 0 || strncmp("..\\", fname, 3) == 0)
-      return (char *)fname;
-    if (exe_flag && strchr(fname, '\\')) return (char *)fname;
+    switch (*p) {
+      case '/': case '\\':
+	is_abs = 1;
+	p++;
+    }
+    has_path = is_abs;
+    while (*p) {
+	switch (*p) {
+	  case '/': case '\\':
+	    has_path = 1;
+	    ext = 0;
+	    p++;
+	    break;
+	  case '.':
+	    ext = p;
+	    p++;
+	    break;
+	  default:
+	    p = CharNext(p);
+	}
+    }
+    if (ext) {
+	for (j = 0; strcasecmp(ext, extension[j]); ) {
+	    if (++j == sizeof(extension) / sizeof(extension[0])) {
+		ext = 0;
+		break;
+	    }
+	}
+    }
+    ep = bp = 0;
+    if (!exe_flag) {
+	RETURN_IF(is_abs);
+    }
+    else if (has_path) {
+	RETURN_IF(ext);
+	i = p - fname;
+	if (i + 1 > size) goto toolong;
+	fspace = size - i - 1;
+	bp = fbuf;
+	ep = p;
+	memcpy(fbuf, fname, i + 1);
+	goto needs_extension;
+    }
 #endif
 
+    RETURN_IF(fname[0] == '/');
+    RETURN_IF(strncmp("./", fname, 2) == 0 || strncmp("../", fname, 3) == 0);
+    RETURN_IF(exe_flag && strchr(fname, '/'));
+
+#undef RETURN_IF
+
     for (dp = path;; dp = ++ep) {
-	register int l;
-	int i;
-	int fspace;
+	register size_t l;
 
 	/* extract a component */
 	ep = strchr(dp, PATH_SEP[0]);
@@ -1730,7 +1782,7 @@ dln_find_1(fname, path, exe_flag)
 	/* find the length of that component */
 	l = ep - dp;
 	bp = fbuf;
-	fspace = sizeof fbuf - 2;
+	fspace = size - 2;
 	if (l > 0) {
 	    /*
 	    **	If the length of the component is zero length,
@@ -1742,7 +1794,7 @@ dln_find_1(fname, path, exe_flag)
 
 	    if (*dp == '~' && (l == 1 ||
 #if defined(DOSISH)
-			       dp[1] == '\\' || 
+			       dp[1] == '\\' ||
 #endif
 			       dp[1] == '/')) {
 		char *home;
@@ -1750,8 +1802,9 @@ dln_find_1(fname, path, exe_flag)
 		home = getenv("HOME");
 		if (home != NULL) {
 		    i = strlen(home);
-		    if ((fspace -= i) < 0)
+		    if (fspace < i)
 			goto toolong;
+		    fspace -= i;
 		    memcpy(bp, home, i);
 		    bp += i;
 		}
@@ -1759,8 +1812,9 @@ dln_find_1(fname, path, exe_flag)
 		l--;
 	    }
 	    if (l > 0) {
-		if ((fspace -= l) < 0)
+		if (fspace < l)
 		    goto toolong;
+		fspace -= l;
 		memcpy(bp, dp, l);
 		bp += l;
 	    }
@@ -1772,7 +1826,7 @@ dln_find_1(fname, path, exe_flag)
 
 	/* now append the file name */
 	i = strlen(fname);
-	if ((fspace -= i) < 0) {
+	if (fspace < i) {
 	  toolong:
 	    fprintf(stderr, "openpath: pathname too long (ignored)\n");
 	    *bp = '\0';
@@ -1780,26 +1834,12 @@ dln_find_1(fname, path, exe_flag)
 	    fprintf(stderr, "\tFile \"%s\"\n", fname);
 	    goto next;
 	}
+	fspace -= i;
 	memcpy(bp, fname, i + 1);
 
 #if defined(DOSISH)
-	if (exe_flag) {
-	    static const char extension[][5] = {
-#if defined(MSDOS)
-		".com", ".exe", ".bat",
-#if defined(DJGPP)
-		".btm", ".sh", ".ksh", ".pl", ".sed",
-#endif
-#elif defined(__EMX__) || defined(_WIN32)
-		".exe", ".com", ".cmd", ".bat",
-/* end of __EMX__ or _WIN32 */
-#else
-		".r", ".R", ".x", ".X", ".bat", ".BAT",
-/* __human68k__ */
-#endif
-	    };
-	    int j;
-
+	if (exe_flag && !ext) {
+	  needs_extension:
 	    for (j = 0; j < sizeof(extension) / sizeof(extension[0]); j++) {
 		if (fspace < strlen(extension[j])) {
 		    fprintf(stderr, "openpath: pathname too long (ignored)\n");
@@ -1808,37 +1848,19 @@ dln_find_1(fname, path, exe_flag)
 		    continue;
 		}
 		strcpy(bp + i, extension[j]);
-#ifndef __MACOS__
 		if (stat(fbuf, &st) == 0)
 		    return fbuf;
-#else
-		if (mac_fullpath = _macruby_exist_file_in_libdir_as_posix_name(fbuf))
-		    return mac_fullpath;
-
-#endif
 	    }
 	    goto next;
 	}
-#endif /* MSDOS or _WIN32 or __human68k__ or __EMX__ */
+#endif /* _WIN32 or __EMX__ */
 
-#ifndef __MACOS__
 	if (stat(fbuf, &st) == 0) {
 	    if (exe_flag == 0) return fbuf;
 	    /* looking for executable */
 	    if (!S_ISDIR(st.st_mode) && eaccess(fbuf, X_OK) == 0)
 		return fbuf;
 	}
-#else
-	if (mac_fullpath = _macruby_exist_file_in_libdir_as_posix_name(fbuf)) {
-	    if (exe_flag == 0) return mac_fullpath;
-	    /* looking for executable */
-	    if (stat(mac_fullpath, &st) == 0) {
-		if (!S_ISDIR(st.st_mode) && eaccess(mac_fullpath, X_OK) == 0)
-		    return mac_fullpath;
-	    }
-	}
-#endif
-
       next:
 	/* if not, and no other alternatives, life is bleak */
 	if (*ep == '\0') {