diff options
Diffstat (limited to 'libblkid/read.c')
-rw-r--r-- | libblkid/read.c | 500 |
1 files changed, 0 insertions, 500 deletions
diff --git a/libblkid/read.c b/libblkid/read.c deleted file mode 100644 index 8914cad69..000000000 --- a/libblkid/read.c +++ /dev/null @@ -1,500 +0,0 @@ -/* - * read.c - read the blkid cache from disk, to avoid scanning all devices - * - * Copyright (C) 2001, 2003 Theodore Y. Ts'o - * Copyright (C) 2001 Andreas Dilger - * - * %Begin-Header% - * This file may be redistributed under the terms of the - * GNU Lesser General Public License. - * %End-Header% - */ - - -#include <stdio.h> -#include <ctype.h> -#include <string.h> -#include <time.h> -#include <sys/types.h> -#include <sys/stat.h> -#include <fcntl.h> -#include <unistd.h> -#ifdef HAVE_ERRNO_H -#include <errno.h> -#endif - -#include "blkidP.h" - -#ifdef HAVE_STDLIB_H -# ifndef _XOPEN_SOURCE -# define _XOPEN_SOURCE 600 /* for inclusion of strtoull */ -# endif -# include <stdlib.h> -#endif - -#ifdef HAVE_STRTOULL -#define STRTOULL strtoull /* defined in stdlib.h if you try hard enough */ -#else -/* FIXME: need to support real strtoull here */ -#define STRTOULL strtoul -#endif - -#ifdef TEST_PROGRAM -#define blkid_debug_dump_dev(dev) (debug_dump_dev(dev)) -static void debug_dump_dev(blkid_dev dev); -#endif - -/* - * File format: - * - * <device [<NAME="value"> ...]>device_name</device> - * - * The following tags are required for each entry: - * <ID="id"> unique (within this file) ID number of this device - * <TIME="sec.usec"> (time_t and suseconds_t) time this entry was last - * read from disk - * <TYPE="type"> (detected) type of filesystem/data for this partition - * - * The following tags may be present, depending on the device contents - * <LABEL="label"> (user supplied) label (volume name, etc) - * <UUID="uuid"> (generated) universally unique identifier (serial no) - */ - -static char *skip_over_blank(char *cp) -{ - while (*cp && isspace(*cp)) - cp++; - return cp; -} - -static char *skip_over_word(char *cp) -{ - char ch; - - while ((ch = *cp)) { - /* If we see a backslash, skip the next character */ - if (ch == '\\') { - cp++; - if (*cp == '\0') - break; - cp++; - continue; - } - if (isspace(ch) || ch == '<' || ch == '>') - break; - cp++; - } - return cp; -} - -static char *strip_line(char *line) -{ - char *p; - - line = skip_over_blank(line); - - p = line + strlen(line) - 1; - - while (*line) { - if (isspace(*p)) - *p-- = '\0'; - else - break; - } - - return line; -} - -#if 0 -static char *parse_word(char **buf) -{ - char *word, *next; - - word = *buf; - if (*word == '\0') - return NULL; - - word = skip_over_blank(word); - next = skip_over_word(word); - if (*next) { - char *end = next - 1; - if (*end == '"' || *end == '\'') - *end = '\0'; - *next++ = '\0'; - } - *buf = next; - - if (*word == '"' || *word == '\'') - word++; - return word; -} -#endif - -/* - * Start parsing a new line from the cache. - * - * line starts with "<device" return 1 -> continue parsing line - * line starts with "<foo", empty, or # return 0 -> skip line - * line starts with other, return -BLKID_ERR_CACHE -> error - */ -static int parse_start(char **cp) -{ - char *p; - - p = strip_line(*cp); - - /* Skip comment or blank lines. We can't just NUL the first '#' char, - * in case it is inside quotes, or escaped. - */ - if (*p == '\0' || *p == '#') - return 0; - - if (!strncmp(p, "<device", 7)) { - DBG(DEBUG_READ, printf("found device header: %8s\n", p)); - p += 7; - - *cp = p; - return 1; - } - - if (*p == '<') - return 0; - - return -BLKID_ERR_CACHE; -} - -/* Consume the remaining XML on the line (cosmetic only) */ -static int parse_end(char **cp) -{ - *cp = skip_over_blank(*cp); - - if (!strncmp(*cp, "</device>", 9)) { - DBG(DEBUG_READ, printf("found device trailer %9s\n", *cp)); - *cp += 9; - return 0; - } - - return -BLKID_ERR_CACHE; -} - -/* - * Allocate a new device struct with device name filled in. Will handle - * finding the device on lines of the form: - * <device foo=bar>devname</device> - * <device>devname<foo>bar</foo></device> - */ -static int parse_dev(blkid_cache cache, blkid_dev *dev, char **cp) -{ - char *start, *tmp, *end, *name; - int ret; - - if ((ret = parse_start(cp)) <= 0) - return ret; - - start = tmp = strchr(*cp, '>'); - if (!start) { - DBG(DEBUG_READ, - printf("blkid: short line parsing dev: %s\n", *cp)); - return -BLKID_ERR_CACHE; - } - start = skip_over_blank(start + 1); - end = skip_over_word(start); - - DBG(DEBUG_READ, printf("device should be %*s\n", - (int)(end - start), start)); - - if (**cp == '>') - *cp = end; - else - (*cp)++; - - *tmp = '\0'; - - if (!(tmp = strrchr(end, '<')) || parse_end(&tmp) < 0) { - DBG(DEBUG_READ, - printf("blkid: missing </device> ending: %s\n", end)); - } else if (tmp) - *tmp = '\0'; - - if (end - start <= 1) { - DBG(DEBUG_READ, printf("blkid: empty device name: %s\n", *cp)); - return -BLKID_ERR_CACHE; - } - - name = strndup(start, end - start); - if (name == NULL) - return -BLKID_ERR_MEM; - - DBG(DEBUG_READ, printf("found dev %s\n", name)); - - if (!(*dev = blkid_get_dev(cache, name, BLKID_DEV_CREATE))) { - free(name); - return -BLKID_ERR_MEM; - } - - free(name); - return 1; -} - -/* - * Extract a tag of the form NAME="value" from the line. - */ -static int parse_token(char **name, char **value, char **cp) -{ - char *end; - - if (!name || !value || !cp) - return -BLKID_ERR_PARAM; - - if (!(*value = strchr(*cp, '='))) - return 0; - - **value = '\0'; - *name = strip_line(*cp); - *value = skip_over_blank(*value + 1); - - if (**value == '"') { - end = strchr(*value + 1, '"'); - if (!end) { - DBG(DEBUG_READ, - printf("unbalanced quotes at: %s\n", *value)); - *cp = *value; - return -BLKID_ERR_CACHE; - } - (*value)++; - *end = '\0'; - end++; - } else { - end = skip_over_word(*value); - if (*end) { - *end = '\0'; - end++; - } - } - *cp = end; - - return 1; -} - -/* - * Extract a tag of the form <NAME>value</NAME> from the line. - */ -/* -static int parse_xml(char **name, char **value, char **cp) -{ - char *end; - - if (!name || !value || !cp) - return -BLKID_ERR_PARAM; - - *name = strip_line(*cp); - - if ((*name)[0] != '<' || (*name)[1] == '/') - return 0; - - FIXME: finish this. -} -*/ - -/* - * Extract a tag from the line. - * - * Return 1 if a valid tag was found. - * Return 0 if no tag found. - * Return -ve error code. - */ -static int parse_tag(blkid_cache cache, blkid_dev dev, char **cp) -{ - char *name = NULL; - char *value = NULL; - int ret; - - if (!cache || !dev) - return -BLKID_ERR_PARAM; - - if ((ret = parse_token(&name, &value, cp)) <= 0 /* && - (ret = parse_xml(&name, &value, cp)) <= 0 */) - return ret; - - /* Some tags are stored directly in the device struct */ - if (!strcmp(name, "DEVNO")) - dev->bid_devno = STRTOULL(value, 0, 0); - else if (!strcmp(name, "PRI")) - dev->bid_pri = strtol(value, 0, 0); - else if (!strcmp(name, "TIME")) { - char *end = NULL; - dev->bid_time = STRTOULL(value, &end, 0); - if (end && *end == '.') - dev->bid_utime = STRTOULL(end + 1, 0, 0); - } else - ret = blkid_set_tag(dev, name, value, strlen(value)); - - DBG(DEBUG_READ, printf(" tag: %s=\"%s\"\n", name, value)); - - return ret < 0 ? ret : 1; -} - -/* - * Parse a single line of data, and return a newly allocated dev struct. - * Add the new device to the cache struct, if one was read. - * - * Lines are of the form <device [TAG="value" ...]>/dev/foo</device> - * - * Returns -ve value on error. - * Returns 0 otherwise. - * If a valid device was read, *dev_p is non-NULL, otherwise it is NULL - * (e.g. comment lines, unknown XML content, etc). - */ -static int blkid_parse_line(blkid_cache cache, blkid_dev *dev_p, char *cp) -{ - blkid_dev dev; - int ret; - - if (!cache || !dev_p) - return -BLKID_ERR_PARAM; - - *dev_p = NULL; - - DBG(DEBUG_READ, printf("line: %s\n", cp)); - - if ((ret = parse_dev(cache, dev_p, &cp)) <= 0) - return ret; - - dev = *dev_p; - - while ((ret = parse_tag(cache, dev, &cp)) > 0) { - ; - } - - if (dev->bid_type == NULL) { - DBG(DEBUG_READ, - printf("blkid: device %s has no TYPE\n",dev->bid_name)); - blkid_free_dev(dev); - goto done; - } - - DBG(DEBUG_READ, blkid_debug_dump_dev(dev)); - -done: - return ret; -} - -/* - * Parse the specified filename, and return the data in the supplied or - * a newly allocated cache struct. If the file doesn't exist, return a - * new empty cache struct. - */ -void blkid_read_cache(blkid_cache cache) -{ - FILE *file; - char buf[4096]; - int fd, lineno = 0; - struct stat st; - - if (!cache) - return; - - /* - * If the file doesn't exist, then we just return an empty - * struct so that the cache can be populated. - */ - if ((fd = open(cache->bic_filename, O_RDONLY|O_CLOEXEC)) < 0) - return; - if (fstat(fd, &st) < 0) - goto errout; - if ((st.st_mtime == cache->bic_ftime) || - (cache->bic_flags & BLKID_BIC_FL_CHANGED)) { - DBG(DEBUG_CACHE, printf("skipping re-read of %s\n", - cache->bic_filename)); - goto errout; - } - - DBG(DEBUG_CACHE, printf("reading cache file %s\n", - cache->bic_filename)); - - file = fdopen(fd, "r"); - if (!file) - goto errout; - - while (fgets(buf, sizeof(buf), file)) { - blkid_dev dev; - unsigned int end; - - lineno++; - if (buf[0] == 0) - continue; - end = strlen(buf) - 1; - /* Continue reading next line if it ends with a backslash */ - while (end < (sizeof(buf) - 2) && buf[end] == '\\' && - fgets(buf + end, sizeof(buf) - end, file)) { - end = strlen(buf) - 1; - lineno++; - } - - if (blkid_parse_line(cache, &dev, buf) < 0) { - DBG(DEBUG_READ, - printf("blkid: bad format on line %d\n", lineno)); - continue; - } - } - fclose(file); - - /* - * Initially we do not need to write out the cache file. - */ - cache->bic_flags &= ~BLKID_BIC_FL_CHANGED; - cache->bic_ftime = st.st_mtime; - - return; -errout: - close(fd); - return; -} - -#ifdef TEST_PROGRAM -static void debug_dump_dev(blkid_dev dev) -{ - struct list_head *p; - - if (!dev) { - printf(" dev: NULL\n"); - return; - } - - printf(" dev: name = %s\n", dev->bid_name); - printf(" dev: DEVNO=\"0x%0llx\"\n", (long long)dev->bid_devno); - printf(" dev: TIME=\"%ld.%ld\"\n", (long)dev->bid_time, (long)dev->bid_utime); - printf(" dev: PRI=\"%d\"\n", dev->bid_pri); - printf(" dev: flags = 0x%08X\n", dev->bid_flags); - - list_for_each(p, &dev->bid_tags) { - blkid_tag tag = list_entry(p, struct blkid_struct_tag, bit_tags); - if (tag) - printf(" tag: %s=\"%s\"\n", tag->bit_name, - tag->bit_val); - else - printf(" tag: NULL\n"); - } - printf("\n"); -} - -int main(int argc, char**argv) -{ - blkid_cache cache = NULL; - int ret; - - blkid_init_debug(DEBUG_ALL); - if (argc > 2) { - fprintf(stderr, "Usage: %s [filename]\n" - "Test parsing of the cache (filename)\n", argv[0]); - exit(1); - } - if ((ret = blkid_get_cache(&cache, argv[1])) < 0) - fprintf(stderr, "error %d reading cache file %s\n", ret, - argv[1] ? argv[1] : blkid_get_cache_filename(NULL)); - - blkid_put_cache(cache); - - return ret; -} -#endif |