diff options
Diffstat (limited to 'contrib/android/base_fs.c')
| -rw-r--r-- | contrib/android/base_fs.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/contrib/android/base_fs.c b/contrib/android/base_fs.c new file mode 100644 index 0000000..d3e00d1 --- /dev/null +++ b/contrib/android/base_fs.c @@ -0,0 +1,211 @@ +#include "base_fs.h" +#include <stdio.h> + +#define BASE_FS_VERSION "Base EXT4 version 1.0" + +struct base_fs { + FILE *file; + const char *mountpoint; + struct basefs_entry entry; +}; + +static FILE *basefs_open(const char *file) +{ + char *line = NULL; + size_t len; + FILE *f = fopen(file, "r"); + if (!f) + return NULL; + + if (getline(&line, &len, f) == -1 || !line) + goto err_getline; + + if (strncmp(line, BASE_FS_VERSION, strlen(BASE_FS_VERSION))) + goto err_header; + + free(line); + return f; + +err_header: + free(line); +err_getline: + fclose(f); + return NULL; +} + +static struct basefs_entry *basefs_readline(FILE *f, const char *mountpoint, + int *err) +{ + char *line = NULL, *saveptr1, *saveptr2, *block_range, *block; + int offset; + size_t len; + struct basefs_entry *entry = NULL; + blk64_t range_start, range_end; + + if (getline(&line, &len, f) == -1) { + if (feof(f)) + goto end; + goto err_getline; + } + + entry = calloc(1, sizeof(*entry)); + if (!entry) + goto err_alloc; + + /* + * With BASEFS version 1.0, a typical line looks like this: + * /bin/mke2fs 5000-5004,8000,9000-9990 + */ + if (sscanf(line, "%ms%n", &entry->path, &offset) != 1) + goto err_sscanf; + len = strlen(mountpoint); + memmove(entry->path, entry->path + len, strlen(entry->path) - len + 1); + + while (line[offset] == ' ') + ++offset; + + block_range = strtok_r(line + offset, ",\n", &saveptr1); + while (block_range) { + block = strtok_r(block_range, "-", &saveptr2); + if (!block) + break; + range_start = atoll(block); + block = strtok_r(NULL, "-", &saveptr2); + range_end = block ? atoll(block) : range_start; + add_blocks_to_range(&entry->blocks, range_start, range_end); + block_range = strtok_r(NULL, ",\n", &saveptr1); + } +end: + *err = 0; + free(line); + return entry; + +err_sscanf: + free(entry); +err_alloc: + free(line); +err_getline: + *err = 1; + return NULL; +} + +static void free_base_fs_entry(void *e) +{ + struct basefs_entry *entry = e; + if (entry) { + free(entry->path); + free(entry); + } +} + +struct ext2fs_hashmap *basefs_parse(const char *file, const char *mountpoint) +{ + int err; + struct ext2fs_hashmap *entries = NULL; + struct basefs_entry *entry; + FILE *f = basefs_open(file); + if (!f) + return NULL; + entries = ext2fs_hashmap_create(ext2fs_djb2_hash, free_base_fs_entry, 1024); + if (!entries) + goto end; + + while ((entry = basefs_readline(f, mountpoint, &err))) { + err = ext2fs_hashmap_add(entries, entry, entry->path, + strlen(entry->path)); + if (err) { + free_base_fs_entry(entry); + fclose(f); + ext2fs_hashmap_free(entries); + return NULL; + } + } + if (err) { + fclose(f); + ext2fs_hashmap_free(entries); + return NULL; + } +end: + fclose(f); + return entries; +} + +static void *init(const char *file, const char *mountpoint) +{ + struct base_fs *params = malloc(sizeof(*params)); + + if (!params) + return NULL; + params->mountpoint = mountpoint; + params->file = fopen(file, "w+"); + if (!params->file) { + free(params); + return NULL; + } + if (fwrite(BASE_FS_VERSION"\n", 1, strlen(BASE_FS_VERSION"\n"), + params->file) != strlen(BASE_FS_VERSION"\n")) { + fclose(params->file); + free(params); + return NULL; + } + return params; +} + +static int start_new_file(char *path, ext2_ino_t ino EXT2FS_ATTR((unused)), + struct ext2_inode *inode, void *data) +{ + struct base_fs *params = data; + + params->entry.path = LINUX_S_ISREG(inode->i_mode) ? path : NULL; + return 0; +} + +static int add_block(ext2_filsys fs EXT2FS_ATTR((unused)), blk64_t blocknr, + int metadata, void *data) +{ + struct base_fs *params = data; + + if (params->entry.path && !metadata) + add_blocks_to_range(¶ms->entry.blocks, blocknr, blocknr); + return 0; +} + +static int inline_data(void *inline_data EXT2FS_ATTR((unused)), + void *data EXT2FS_ATTR((unused))) +{ + return 0; +} + +static int end_new_file(void *data) +{ + struct base_fs *params = data; + + if (!params->entry.path) + return 0; + if (fprintf(params->file, "%s%s ", params->mountpoint, + params->entry.path) < 0 + || write_block_ranges(params->file, params->entry.blocks.head, ",") + || fwrite("\n", 1, 1, params->file) != 1) + return -1; + + delete_block_ranges(¶ms->entry.blocks); + return 0; +} + +static int cleanup(void *data) +{ + struct base_fs *params = data; + + fclose(params->file); + free(params); + return 0; +} + +struct fsmap_format base_fs_format = { + .init = init, + .start_new_file = start_new_file, + .add_block = add_block, + .inline_data = inline_data, + .end_new_file = end_new_file, + .cleanup = cleanup, +}; |