fs: folder support, part 2 (path normalization and root)

include/gint/fs.h

@@ -87,6 +87,26 @@ void fs_free_descriptor(int fd);
    itself. */
 int open_generic(fs_descriptor_type_t *type, void *data, int reuse_fd);
 
+/* fs_path_normalize(): Normalize a path to eliminate ., .. and redundant /
+
+   This function creates a copy of the specified path which is an absolute path
+   with redundant / removed and . and .. components resolved. For instance:
+
+     "" -> "/"
+     "/subfolder/./" -> "/subfolder"
+     "/../subfolder/../subfolder" -> "/subfolder"
+     "/../../x/y/../t" -> "/x/t"
+
+   The new string is created with malloc() and should be free()'d after use. */
+char *fs_path_normalize(char const *path);
+
+/* fs_path_normalize_fc(): Normalize a path and translate it to FONTCHARACTER
+
+   This function is similar to fs_path_normalize(), but it creates a 16-bit
+   string that starts with \\fls0\ rather than /, and can be used in direct
+   calls to BFile. */
+uint16_t *fs_path_normalize_fc(char const *path);
+
 #ifdef __cplusplus
 }
 #endif

src/fs/fugue/fugue_dir.c

@@ -6,6 +6,7 @@
 #include <fcntl.h>
 #include <errno.h>
 #include <stdlib.h>
+#include <string.h>
 #include "util.h"
 #include "fugue.h"
 
@@ -63,7 +64,8 @@ off_t fugue_dir_lseek(void *data, off_t offset, int whence)
 	if(whence == SEEK_END)
 		offset += dp->count;
 
-	if(offset < 0 || offset >= dp->count) {
+	/* dp->count, being at the end of the enumeration, is a valid offset */
+	if(offset < 0 || offset >= dp->count + 1) {
 		errno = EINVAL;
 		return -1;
 	}
@@ -97,6 +99,7 @@ const fs_descriptor_type_t fugue_dir_descriptor_type = {
 void *fugue_dir_explore(char const *path)
 {
 	struct BFile_FileInfo info;
+	char *wildcard=NULL;
 	uint16_t *fc_path=NULL, *search=NULL;
 
 	dir_t *dp = malloc(sizeof *dp);
@@ -111,7 +114,12 @@ void *fugue_dir_explore(char const *path)
 	fc_path = malloc(512 * sizeof *fc_path);
 	if(!fc_path) goto alloc_failure;
 
-	search = utf8_to_fc_alloc(u"\\\\fls0\\", path, u"\\*");
+	wildcard = malloc(strlen(path) + 3);
+	if(!wildcard) goto alloc_failure;
+	strcpy(wildcard, path);
+	strcat(wildcard, "/*");
+
+	search = fs_path_normalize_fc(wildcard);
 	if(!search) goto alloc_failure;
 
 	rc = BFile_FindFirst(search, &sd, fc_path, &info);
@@ -142,6 +150,8 @@ void *fugue_dir_explore(char const *path)
 
 		if(info.type == BFile_Type_File)
 			ent->d_type = DT_REG;
+		if(info.type == BFile_Type_Archived)
+			ent->d_type = DT_REG;
 		if(info.type == BFile_Type_Directory)
 			ent->d_type = DT_DIR;
 		if(info.type == BFile_Type_Dot)
@@ -160,6 +170,7 @@ alloc_failure:
 	errno = ENOMEM;
 	fugue_dir_close(dp);
 end:
+	free(wildcard);
 	free(search);
 	free(fc_path);
 	if(sd >= 0)

src/fs/fugue/fugue_mkdir.c

@@ -1,5 +1,6 @@
 #include <gint/hardware.h>
 #include <gint/bfile.h>
+#include <gint/fs.h>
 #include <errno.h>
 #include "util.h"
 
@@ -7,7 +8,7 @@ int fugue_mkdir(char const *path, GUNUSED mode_t mode)
 {
 	ENOTSUP_IF_NOT_FUGUE(-1);
 
-	uint16_t *fcpath = utf8_to_fc_alloc(u"\\\\fls0\\", path, NULL);
+	uint16_t *fcpath = fs_path_normalize_fc(path);
 	if(!fcpath) {
 		errno = ENOMEM;
 		return -1;
@@ -16,8 +17,10 @@ int fugue_mkdir(char const *path, GUNUSED mode_t mode)
 	int rc = BFile_Create(fcpath, BFile_Folder, NULL);
 	if(rc < 0) {
 		errno = bfile_error_to_errno(rc);
+		free(fcpath);
 		return -1;
 	}
 
+	free(fcpath);
 	return 0;
 }

src/fs/fugue/fugue_open.c

@@ -2,6 +2,7 @@
 #include <gint/bfile.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <string.h>
 #include "util.h"
 #include "fugue.h"
 
@@ -11,7 +12,7 @@ int fugue_open(char const *path, int flags, GUNUSED mode_t mode)
 {
 	ENOTSUP_IF_NOT_FUGUE(-1);
 
-	uint16_t *fcpath = utf8_to_fc_alloc(u"\\\\fls0\\", path, NULL);
+	uint16_t *fcpath = fs_path_normalize_fc(path);
 	int fugue_fd, err, rc=-1, type, fd=-1;
 
 	if(!fcpath) {
@@ -31,21 +32,32 @@ int fugue_open(char const *path, int flags, GUNUSED mode_t mode)
 	/* Truncation requires the file to be removed/recreated */
 	bool trunc = (flags & O_TRUNC) && (flags & O_CREAT);
 
-	/* Stat the entry */
+	/* Stat the entry. A special case is needed for the root, which doesn't
-	bool exists = (BFile_Ext_Stat(fcpath, &type, NULL) == 0);
+	   respond well. fs_path_normalize_fc() normalizes the path so we just
+	   have to check for the fixed string "\\fls0\". */
+	bool exists;
+	if(!memcmp(fcpath, u"\\\\fls0\\", 16)) {
+		exists = true;
+		type = BFile_Type_Directory;
+	}
+	else {
+		exists = (BFile_Ext_Stat(fcpath, &type, NULL) == 0);
 		if(!exists) type = -1;
+	}
 
 	/* If the entry exists and O_EXCL was requested, fail. */
 	if(exists && excl) {
 		errno = EEXIST;
-		return -1;
+		rc = -1;
+		goto end;
 	}
 
 	/* If the entry is not a directory but O_DIRECTORY is set, fail. If the
 	   directory doesn't exist, we fail regardless of O_CREAT. */
 	if((flags & O_DIRECTORY) && type != BFile_Type_Directory) {
 		errno = (exists ? ENOTDIR : ENOENT);
-		return -1;
+		rc = -1;
+		goto end;
 	}
 
 	/* If the entry is a directory, open it as such */
@@ -83,6 +95,7 @@ int fugue_open(char const *path, int flags, GUNUSED mode_t mode)
 		err = BFile_Create(fcpath, BFile_File, &size);
 		if(err < 0) {
 			errno = bfile_error_to_errno(err);
+			rc = -1;
 			goto end;
 		}
 		fugue_fd = BFile_Open(fcpath, bfile_mode);
@@ -104,7 +117,7 @@ int fugue_open(char const *path, int flags, GUNUSED mode_t mode)
 		.type = &fugue_descriptor_type,
 		.data = (void *)fugue_fd,
 	};
-	fd = fs_create_descriptor(&data);
+	rc = fd = fs_create_descriptor(&data);
 
 	if(fd == -1) {
 		BFile_Close(fugue_fd);
@@ -112,7 +125,6 @@ int fugue_open(char const *path, int flags, GUNUSED mode_t mode)
 		goto end;
 	}
 
-	rc = fd;
 end:
 	free(fcpath);
 	return rc;

src/fs/fugue/fugue_unlink.c

@@ -1,5 +1,6 @@
 #include <gint/hardware.h>
 #include <gint/bfile.h>
+#include <gint/fs.h>
 #include <errno.h>
 #include "util.h"
 
@@ -7,7 +8,7 @@ int fugue_unlink(char const *path)
 {
 	ENOTSUP_IF_NOT_FUGUE(-1);
 
-	uint16_t *fcpath = utf8_to_fc_alloc(u"\\\\fls0\\", path, NULL);
+	uint16_t *fcpath = fs_path_normalize_fc(path);
 	if(!fcpath) {
 		errno = ENOMEM;
 		return -1;
@@ -16,9 +17,11 @@ int fugue_unlink(char const *path)
 	int err = BFile_Remove(fcpath);
 	if(err < 0) {
 		errno = bfile_error_to_errno(err);
+		free(fcpath);
 		return -1;
 	}
 
+	free(fcpath);
 	return 0;
 }
 

src/fs/fugue/util.c

@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <errno.h>
+#include <stdarg.h>
 #include <gint/bfile.h>
 
 int bfile_error_to_errno(int e)
@@ -52,7 +53,7 @@ void utf8_to_fc(uint16_t *fc, char const *utf8, size_t fc_len)
 			fc[j++] = utf8[i];
 	}
 
-	while(j < fc_len)
+	if(j < fc_len)
 		fc[j++] = 0;
 }
 
@@ -67,7 +68,7 @@ void fc_to_utf8(char *utf8, uint16_t const *fc, size_t utf8_len)
 			utf8[j++] = fc[i];
 	}
 
-	while(j < utf8_len)
+	if(j < utf8_len)
 		utf8[j++] = 0;
 }
 
@@ -106,3 +107,111 @@ char *fc_to_utf8_alloc(uint16_t const *fc)
 		fc_to_utf8(utf8, fc, len+1);
 	return utf8;
 }
+
+/* Split a path into components. Only the top array needs to be freed */
+char **fs_split_components(char *path, int *count)
+{
+	char **comps = NULL;
+	*count = 0;
+	int allocated = 0;
+
+	char *token = strtok(path, "/");
+
+	while(token) {
+		if(*count + 1 > allocated) {
+			allocated += 8;
+			char **new_comps = realloc(comps,
+				allocated * sizeof *comps);
+			if(!new_comps) {
+				*count = -1;
+				return NULL;
+			}
+			comps = new_comps;
+		}
+		comps[*count] = token;
+		*count += 1;
+
+		token = strtok(NULL, "/");
+	}
+
+	return comps;
+}
+
+/* Generalization of fs_path_normalize(). Returns a [char *] if use_fc=false,
+   otherwise returns an [uint16_t *]. */
+static void *path_normalize(char const *path, bool use_fc)
+{
+	char *path_dup = strdup(path);
+	if(!path_dup) return NULL;
+
+	int components=0;
+	char **comps = fs_split_components(path_dup, &components);
+	if(components == -1) {
+		free(path_dup);
+		return NULL;
+	}
+
+	/* Now rewrite comps[] to skip "." and apply ".." */
+	int wr = 0;
+	for(int rd=0; rd < components; rd++) {
+		char *comp = comps[rd];
+		if(!strcmp(comp, "."))
+			continue;
+		else if(!strcmp(comp, ".."))
+			wr -= (wr > 0);
+		else
+			comps[wr++] = comp;
+	}
+
+	/* Count total length */
+	int length = (use_fc ? 7 : 1) + (wr >= 1 ? wr - 1 : 0);
+	for(int i = 0; i < wr; i++) {
+		length += utf8_len(comps[i]);
+	}
+
+	/* Allocate string then copy */
+	if(use_fc) {
+		uint16_t *fc = malloc((length + 1) * sizeof *fc);
+		uint16_t *fc_init = fc;
+
+		memcpy(fc, u"\\\\fls0\\", 7*2);
+		fc += 7;
+
+		for(int i = 0; i < wr; i++) {
+			if(i > 0) *fc++ = '\\';
+			utf8_to_fc(fc, comps[i], (size_t)-1);
+			fc += utf8_len(comps[i]);
+		}
+
+		*fc++ = 0;
+		free(path_dup);
+		free(comps);
+		return fc_init;
+	}
+	else {
+		char *utf8 = malloc(length + 1);
+		char *utf8_init = utf8;
+		*utf8++ = '/';
+
+		for(int i = 0; i < wr; i++) {
+			if(i > 0) *utf8++ = '/';
+			strcpy(utf8, comps[i]);
+			utf8 += utf8_len(comps[i]);
+		}
+
+		*utf8++ = 0;
+		free(path_dup);
+		free(comps);
+		return utf8_init;
+	}
+}
+
+char *fs_path_normalize(char const *path)
+{
+	return path_normalize(path, false);
+}
+
+uint16_t *fs_path_normalize_fc(char const *path)
+{
+	return path_normalize(path, true);
+}

src/fs/fugue/util.h

@@ -14,7 +14,7 @@ extern "C" {
    if(gint[HWFS] != HWFS_FUGUE) { errno = ENOTSUP; return (rc); }
 
 /* Translate common BFile error codes to errno values. */
-extern int bfile_error_to_errno(int bfile_error_code);
+int bfile_error_to_errno(int bfile_error_code);
 
 /* TODO: These functions do not actually translate special characters between
    encodings, they simply strip them. */
@@ -26,17 +26,17 @@ size_t fc_len(uint16_t const *fc);
 
 /* Convert UTF-8 to FONTCHARACTER; outputs fc_len characters with padding. If
    fc[fc_len-1] is not 0 after the call, then fc is too short. */
-extern void utf8_to_fc(uint16_t *fc, char const *utf8, size_t fc_len);
+void utf8_to_fc(uint16_t *fc, char const *utf8, size_t fc_len);
 
 /* Same in the other direction. */
-extern void fc_to_utf8(char *utf8, uint16_t const *fc, size_t utf8_len);
+void fc_to_utf8(char *utf8, uint16_t const *fc, size_t utf8_len);
 
 /* Same as utf8_to_fc() but allocates a string with malloc(). */
-extern uint16_t *utf8_to_fc_alloc(uint16_t *prefix, char const *utf8,
+uint16_t *utf8_to_fc_alloc(uint16_t *prefix, char const *utf8,
    uint16_t *suffix);
 
 /* Same as fc_to_utf8() but allocates a string with malloc(). */
-extern char *fc_to_utf8_alloc(uint16_t const *fc);
+char *fc_to_utf8_alloc(uint16_t const *fc);
 
 #ifdef __cplusplus
 }