Fixed disk reading

boot/common/fs/uefi_sfs.c

@@ -95,7 +95,7 @@ struct vfs_drive *sfs_init(char *mountpoint)
 	return drive;
 }
 
-size_t sfs_read(char *filename, char *buffer, struct vfs_drive *dev, void *fsdata)
+size_t sfs_read(char *filename, char **buffer, struct vfs_drive *dev, void *fsdata)
 {
 	struct sfs_fsdata *data = (struct sfs_fsdata *)fsdata;
 	EFI_FILE_PROTOCOL *volume = data->volume;
@@ -113,7 +113,8 @@ size_t sfs_read(char *filename, char *buffer, struct vfs_drive *dev, void *fsdat
 		return 0;
 	}
 
-	mbstowcs(wfilename, (const char **)&filename, strlen(filename));
+	size_t n = mbstowcs(wfilename, (const char **)&filename, strlen(filename));
+	wfilename[n] = L'\0';
 
 	/* open the file */
 	status = volume->Open(volume, &file, wfilename, EFI_FILE_MODE_READ, EFI_FILE_READ_ONLY | EFI_FILE_HIDDEN | EFI_FILE_SYSTEM);
@@ -134,16 +135,19 @@ size_t sfs_read(char *filename, char *buffer, struct vfs_drive *dev, void *fsdat
 
 	file->GetInfo(file, &fi_guid, &fileinfo_size, fileinfo);
 	len = fileinfo->FileSize;
+	mem_free(fileinfo);
 
-	debug("sfs_read: %u\n", len);
+	*buffer = (char *)mem_alloc(len * sizeof(char));
-
+	if (!*buffer) {
-	buffer = (char *)mem_alloc(len * sizeof(char));
-	if (!buffer) {
 		debug("sfs_read(): Failed to allocate memory for output buffer!\n");
 		return 0;
 	}
 
-	file->Read(file, &len, buffer);
+	status = file->Read(file, &len, *buffer);
+	if (EFI_ERROR(status)) {
+		debug("sfs_read(): Failed to read file '%s': %s (%lx)\n", filename, efi_status_to_str(status), status);
+		return 0;
+	}
 
 	/* close the file */
 	file->Close(file);

boot/common/init.c

@@ -31,7 +31,9 @@ void axboot_init()
 
 	// read kernel -> test read
 	char *buffer = NULL;
-	vfs_read("\\System\\axkrnl", buffer);
+	vfs_read("\\System\\axkrnl", &buffer);
+
+	// TODO: Do something with the kernel :p
 
 	mem_free(buffer);
 

boot/common/lib/string.c

@@ -32,7 +32,7 @@ size_t mbstowcs(wchar_t *dest, const char **src, size_t len)
 		return 0;
 	}
 
-	while (count--) {
+	while (count) {
 		if ((*dest = *lsrc) == 0) {
 			lsrc = NULL;
 			break;
@@ -44,6 +44,7 @@ size_t mbstowcs(wchar_t *dest, const char **src, size_t len)
 
 		lsrc++;
 		dest++;
+		count--;
 	}
 
 	return len - count;

boot/common/vfs/vfs.c

@@ -45,7 +45,7 @@ int vfs_init(char *root_mountpoint)
 	return 1;
 }
 
-size_t vfs_read(char *filename, char *buf)
+size_t vfs_read(char *filename, char **buf)
 {
 	if (boot_drive->fs->read == NULL) {
 		debug("vfs_read(): Filesystem didn't set up a read function!");

boot/include/fs/uefi_sfs.h

@@ -25,6 +25,6 @@
 
 struct vfs_drive *sfs_init(char *mountpoint);
 
-size_t sfs_read(char *filename, char *buffer, struct vfs_drive *dev, void *fsdata);
+size_t sfs_read(char *filename, char **buffer, struct vfs_drive *dev, void *fsdata);
 
 #endif /* _FS_UEFI_SFS_H */

boot/include/vfs/vfs.h

@@ -25,7 +25,7 @@
 #include <stddef.h>
 
 struct vfs_filesystem {
-	size_t (*read)(char *, char *, struct vfs_drive *, void *);
+	size_t (*read)(char *, char **, struct vfs_drive *, void *);
 	uint8_t (*write)(char *, char *, size_t, struct vfs_drive *, void *);
 
 	void *fsdata;
@@ -40,7 +40,7 @@ int vfs_init(char *root_mountpoint);
 
 /* This function allocates `buf`. Passing a non-NULL value will result in an error. */
 /* NOTE: Remember to free the allocated memory afterwards! */
-size_t vfs_read(char *filename, char *buf);
+size_t vfs_read(char *filename, char **buf);
 int vfs_write(char *filename, char *buf, size_t len);
 
 /* Every platform will define this on its own */