virtual_chdir:

* added error handling
* fixed the special case where there were more DIRECTORY_UPs than
  directory parts (i.e. cwd is d:\foo and path is ../..)
* no spaces between # and preprocessor directive - breaks some compilers
# added directory-existence check (not activated)

main/php_virtual_cwd.c

@@ -1,25 +1,86 @@
+#include <sys/types.h>
+#include <sys/stat.h>
 #include <string.h>
 #include <stdio.h>
+#include <unistd.h>
+#include <limits.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <ctype.h>
 
 typedef unsigned int uint;
 
 #if WINDOWS
-# define IS_SLASH(c)	((c) == '/' || (c) == '\\')
-# define DEFAULT_SLASH '\\'
-# define TOKENIZER_STRING "/\\"
+#define IS_SLASH(c)	((c) == '/' || (c) == '\\')
+#define DEFAULT_SLASH '\\'
+#define TOKENIZER_STRING "/\\"
+
+#define IS_ABSOLUTE_PATH(path, len) \
+	(len >= 2 && isalpha(path[0]) && path[1] == ':')
+
+static int php_check_dots(char *element, uint len) 
+{
+	uint n = len;
+
+	while (n-- > 0) if (element[n] != '.') break;
+
+	return (n != -1);
+}
+	
+#define IS_DIRECTORY_UP(element, len) \
+	(len >= 2 && !php_check_dots(element, len))
+
+#define IS_DIRECTORY_CURRENT(element, len) \
+	(len == 1 && ptr[0] == '.')
+
+
 #else
-# define IS_SLASH(c)	((c) == '/')
-# define DEFAULT_SLASH '/'
-# define TOKENIZER_STRING "/"
+#define IS_SLASH(c)	((c) == '/')
+#define DEFAULT_SLASH '/'
+#define TOKENIZER_STRING "/"
 #endif
 
 
+/* default macros */
 
+#ifndef IS_ABSOLUTE_PATH	
+#define IS_ABSOLUTE_PATH(path, len) \
+	(IS_SLASH(path[0]))
+#endif
+
+#ifndef IS_DIRECTORY_UP
+#define IS_DIRECTORY_UP(element, len) \
+	(len == 2 && memcmp(element, "..", 2) == 0)
+#endif
+
+#ifndef IS_DIRECTORY_CURRENT
+#define IS_DIRECTORY_CURRENT(element, len) \
+	(len == 1 && ptr[0] == '.')
+#endif
+
+/* for now */
+#define IS_DIR_OK(s) (1)
+	
+#ifndef IS_DIR_OK
+#define IS_DIR_OK(state) (php_is_dir_ok(state) == 0)
+#endif
+	
 typedef struct _cwd_state {
 	char *cwd;
 	uint cwd_length;
 } cwd_state;
 
+static int php_is_dir_ok(const cwd_state *state) 
+{
+	struct stat buf;
+
+	if (stat(state->cwd, &buf) == 0 && S_ISDIR(buf.st_mode))
+		return (0);
+
+	return (1);
+}
+
+
 char *virtual_getcwd(cwd_state *state, uint *length)
 {
 	if (state->cwd_length == 0) {
@@ -49,60 +110,110 @@ char *virtual_getcwd(cwd_state *state, uint *length)
 	return strdup(state->cwd);
 }
 
-void virtual_chdir(cwd_state *state, char *path)
+/* returns 0 for ok, 1 for error */
+int virtual_chdir(cwd_state *state, char *path)
 {
 	uint path_length = strlen(path);
 	char *ptr = path;
+	char *tok = NULL;
 	uint ptr_length;
+	cwd_state *old_state;
 
-	if (path_length == 0) {
-		return;
-	}
-#if WINDOWS
-	/* Full path includes anything starting with C: */
-	if (IS_SLASH(*ptr) || (path_length >= 2 && path[1] == ':'))
-#else
-	if (IS_SLASH(*ptr))
-#endif
-	{
-		state->cwd = (char *) realloc(state->cwd, 1);
+	if (path_length == 0) 
+		return (0);
+
+	old_state = (cwd_state *) malloc(sizeof(*old_state));
+	old_state->cwd = strdup(state->cwd);
+	old_state->cwd_length = state->cwd_length;
+	
+	if (IS_ABSOLUTE_PATH(path, path_length)) {
+		state->cwd = (char *) malloc(1);
 		state->cwd[0] = '\0';
 		state->cwd_length = 0;
-	}	
+#if WINDOWS
+	} else if(IS_SLASH(path[0])) {
+		state->cwd = (char *) malloc(3);
+		memcpy(state->cwd, old_state->cwd, 2);
+		state->cwd[2] = '\0';
+		state->cwd_length = 2;
+#endif
+	}
 
-	ptr = strtok(path, TOKENIZER_STRING);
-	while(ptr) {
-		ptr_length = strlen(ptr);	
-		if (ptr_length == 2 && !memcmp(ptr, "..", 2)) {
-			while (!IS_SLASH(state->cwd[state->cwd_length-1])) {
-				state->cwd[--(state->cwd_length)] = '\0';
+
+	ptr = strtok_r(path, TOKENIZER_STRING, &tok);
+	while (ptr) {
+		ptr_length = strlen(ptr);
+
+		
+		if (IS_DIRECTORY_UP(ptr, ptr_length)) {
+			char save;
+
+			save = '\0';
+
+#define PREVIOUS state->cwd[state->cwd_length - 1]
+
+			while (IS_ABSOLUTE_PATH(state->cwd, state->cwd_length) &&
+					!IS_SLASH(PREVIOUS)) {
+				save = PREVIOUS;
+				PREVIOUS = '\0';
+				state->cwd_length--;
 			}
-			state->cwd[--(state->cwd_length)] = '\0';
-		} else if (ptr_length == 1 && *ptr == '.') {
-			/* Do nothing */
-		} else {
+
+			if (!IS_ABSOLUTE_PATH(state->cwd, state->cwd_length)) {
+				state->cwd[state->cwd_length++] = save;
+				state->cwd[state->cwd_length] = '\0';
+			} else {
+				PREVIOUS = '\0';
+				state->cwd_length--;
+			}
+		} else if (!IS_DIRECTORY_CURRENT(ptr, ptr_length)) {
 			state->cwd = (char *) realloc(state->cwd, state->cwd_length+ptr_length+1+1);
 			state->cwd[state->cwd_length] = DEFAULT_SLASH;
 			memcpy(&state->cwd[state->cwd_length+1], ptr, ptr_length+1);
 			state->cwd_length += (ptr_length+1);
 		}
-		ptr = strtok(NULL, TOKENIZER_STRING);
+		ptr = strtok_r(NULL, TOKENIZER_STRING, &tok);
 	}
+
+	if (!IS_DIR_OK(state)) {
+		free(state->cwd);
+
+		state->cwd = old_state->cwd;
+		state->cwd_length = state->cwd_length;
+
+		free(old_state);
+
+		return (1);
+	}
+	
+	return (0);
 }
 
-main()
+void main(void)
 {
 	cwd_state state;
 	uint length;
-	
-	state.cwd = strdup("");
-	state.cwd_length = 0;
+
+#if !WINDOWS
+	state.cwd = malloc(PATH_MAX + 1);
+	state.cwd_length = PATH_MAX;
+
+	while (getcwd(state.cwd, state.cwd_length) == NULL && errno == ERANGE) { 
+		state.cwd_length <<= 1;
+		state.cwd = realloc(state.cwd, state.cwd_length + 1);
+	}
+#else
+	state.cwd = strdup("d:\\foo\\bar");
+	state.cwd_length = strlen(state.cwd);
+#endif
 
 	printf("%s\n", virtual_getcwd(&state, &length));
 	virtual_chdir(&state, strdup("/foo/barbara"));
 	printf("%s\n", virtual_getcwd(&state, &length));
 	virtual_chdir(&state, strdup("../andi"));
 	printf("%s\n", virtual_getcwd(&state, &length));
+	virtual_chdir(&state, strdup("../../..../.././.../foo/...../"));
+	printf("%s\n", virtual_getcwd(&state, &length));
 	virtual_chdir(&state, strdup("/////andi"));
 	printf("%s\n", virtual_getcwd(&state, &length));
 	virtual_chdir(&state, strdup("andi/././././././////bar"));