/*
* Copyright (C) 2009 Karel Zak <kzak@redhat.com>
*
* This file may be redistributed under the terms of the
* GNU Lesser General Public License.
*/
#include <string.h>
#include <stdlib.h>
#include <ctype.h>
#include <limits.h>
#include "nls.h"
#include "mountP.h"
static inline char *skip_spaces(char *s)
{
assert(s);
while (*s == ' ' || *s == '\t')
s++;
return s;
}
static inline char *skip_nonspaces(char *s)
{
assert(s);
while (*s && !(*s == ' ' || *s == '\t'))
s++;
return s;
}
#define isoctal(a) (((a) & ~7) == '0')
/* returns malloced pointer - no more strdup required */
static void unmangle(char *s, char *buf, size_t len)
{
size_t sz = 0;
assert(s);
while(*s && sz < len - 1) {
if (*s == '\\' && sz + 4 < len - 1 && isoctal(s[1]) &&
isoctal(s[2]) && isoctal(s[3])) {
*buf++ = 64*(s[1] & 7) + 8*(s[2] & 7) + (s[3] & 7);
s += 4;
sz += 4;
} else {
*buf++ = *s++;
sz++;
}
}
*buf = '\0';
}
static size_t next_word_size(char *s, char **start, char **end)
{
char *e;
assert(s);
s = skip_spaces(s);
if (!*s)
return 0;
e = skip_nonspaces(s);
if (start)
*start = s;
if (end)
*end = e;
return e - s;
}
static char *next_word(char **s)
{
size_t sz;
char *res, *end;
assert(s);
sz = next_word_size(*s, s, &end) + 1;
if (sz == 1)
return NULL;
res = malloc(sz);
if (!res)
return NULL;
unmangle(*s, res, sz);
*s = end + 1;
return res;
}
static int next_word_skip(char **s)
{
*s = skip_spaces(*s);
if (!**s)
return 1;
*s = skip_nonspaces(*s);
return 0;
}
static int next_number(char **s, int *num)
{
char *end = NULL;
assert(num);
assert(s);
*s = skip_spaces(*s);
if (!**s)
return -1;
*num = strtol(*s, &end, 10);
if (end == NULL || *s == end)
return -1;
*s = end;
/* valid end of number is space or terminator */
if (*end == ' ' || *end == '\t' || *end == '\0')
return 0;
return -1;
}
/*
* Parses one line from {fs,m}tab
*/
static int mnt_tab_parse_file_line(mnt_fs *fs, char *s)
{
/* SOURCE */
if (__mnt_fs_set_source(fs, next_word(&s)) != 0)
return 1;
/* TARGET */
fs->target = next_word(&s);
if (!fs->target)
return 1;
/* TYPE */
if (__mnt_fs_set_fstype(fs, next_word(&s)) != 0)
return 1;
/* OPTS */
fs->optstr = next_word(&s);
if (!fs->optstr)
return 1;
/* default */
fs->passno = fs->freq = 0;
/* FREQ (optional) */
if (next_number(&s, &fs->freq) != 0) {
if (*s)
return 1;
/* PASSNO (optional) */
} else if (next_number(&s, &fs->passno) != 0 && *s)
return 1;
return 0;
}
/*
* Parses one line from mountinfo file
*/
static int mnt_parse_mountinfo_line(mnt_fs *fs, char *s)
{
unsigned int maj, min;
/* ID */
if (next_number(&s, &fs->id) != 0)
return 1;
/* PARENT */
if (next_number(&s, &fs->parent) != 0)
return 1;
/* <maj>:<min> */
s = skip_spaces(s);
if (!*s || sscanf(s, "%u:%u", &maj, &min) != 2)
return 1;
fs->devno = makedev(maj, min);
next_word_skip(&s);
/* MOUNTROOT */
fs->mntroot = next_word(&s);
if (!fs->mntroot)
return 1;
/* TARGET (mountpoit) */
fs->target = next_word(&s);
if (!fs->target)
return 1;
/* OPTIONS (fs-independent) */
fs->vfs_optstr = next_word(&s);
if (!fs->vfs_optstr)
return 1;
/* optional fields (ignore) */
do {
s = skip_spaces(s);
if (s && *s == '-' &&
(*(s + 1) == ' ' || *(s + 1) == '\t')) {
s++;
break;
}
if (s && next_word_skip(&s) != 0)
return 1;
} while (s);
/* FSTYPE */
if (__mnt_fs_set_fstype(fs, next_word(&s)) != 0)
return 1;
/* SOURCE or "none" */
if (__mnt_fs_set_source(fs, next_word(&s)) != 0)
return 1;
/* OPTIONS (fs-dependent) */
fs->fs_optstr = next_word(&s);
if (!fs->fs_optstr)
return 1;
return 0;
}
/*
* Returns {m,fs}tab or mountinfo file format (MNT_FMT_*)
*
* The "mountinfo" format is always: "<number> <number> ... "
*/
static int detect_fmt(char *line)
{
int num;
/* ID */
if (next_number(&line, &num) != 0)
return MNT_FMT_FSTAB;
/* PARENT */
if (next_number(&line, &num) != 0)
return MNT_FMT_FSTAB;
return MNT_FMT_MOUNTINFO;
}
/*
* Merges @vfs and @fs options strings into a new string
* This function skips the generic part of @fs options.
* For example (see "rw"):
*
* mnt_merge_optstr("rw,noexec", "rw,journal=update")
*
* returns --> "rw,noexec,journal=update"
*
* We need this function for /proc/self/mountinfo parsing.
*/
static char *merge_optstr(const char *vfs, const char *fs)
{
const char *p1 = vfs, *p2 = fs;
char *res;
size_t sz;
if (!vfs && !fs)
return NULL;
if (!vfs || !fs)
return strdup(fs ? fs : vfs);
if (!strcmp(vfs, fs))
return strdup(vfs); /* e.g. "aaa" and "aaa" */
/* skip the same FS options */
while (*p1 && *p2 && *++p1 == *++p2);
if (*p1 == ',')
p1++;
if (*p2 == ',')
p2++;
if (!*p1 && !*p2) /* e.g. "aaa,bbb" and "aaa,bbb," */
return strdup(vfs);
if (!*p1 || !*p2) /* e.g. "aaa" and "aaa,bbb" */
return strdup(*p1 ? vfs : fs);
p1 = vfs;
sz = strlen(p1) + strlen(p2) + 2; /* 2= separator + '\0' */
res = malloc(sz);
if (!res)
return NULL;
snprintf(res, sz, "%s,%s", p1, p2);
return res;
}
/*
* Read and parse the next line from {fs,m}tab or mountinfo
*/
static int mnt_tab_parse_next(mnt_tab *tb, FILE *f, mnt_fs *fs)
{
char buf[BUFSIZ];
char *s;
assert(tb);
assert(f);
assert(fs);
/* read the next non-blank non-comment line */
do {
if (fgets(buf, sizeof(buf), f) == NULL)
return -1;
tb->nlines++;
s = index (buf, '\n');
if (!s) {
/* Missing final newline? Otherwise extremely */
/* long line - assume file was corrupted */
if (feof(f)) {
DBG(DEBUG_TAB, fprintf(stderr,
"libmount: WARNING: no final newline at the end of %s\n",
tb->filename));
s = index (buf, '\0');
} else {
DBG(DEBUG_TAB, fprintf(stderr,
"libmount: %s: %d: missing newline at line\n",
tb->filename, tb->nlines));
goto err;
}
}
*s = '\0';
if (--s >= buf && *s == '\r')
*s = '\0';
s = skip_spaces(buf);
} while (*s == '\0' || *s == '#');
DBG(DEBUG_TAB, fprintf(stderr, "libmount: %s:%d: %s\n",
tb->filename, tb->nlines, s));
if (!tb->fmt)
tb->fmt = detect_fmt(s);
if (tb->fmt == MNT_FMT_FSTAB) {
/* parse /etc/{fs,m}tab */
if (mnt_tab_parse_file_line(fs, s) != 0)
goto err;
} else if (tb->fmt == MNT_FMT_MOUNTINFO) {
/* parse /proc/self/mountinfo */
if (mnt_parse_mountinfo_line(fs, s) != 0)
goto err;
}
/* merge fs_optstr and vfs_optstr into optstr (necessary for "mountinfo") */
if (!fs->optstr && (fs->vfs_optstr || fs->fs_optstr)) {
fs->optstr = merge_optstr(fs->vfs_optstr, fs->fs_optstr);
if (!fs->optstr)
goto err;
}
fs->lineno = tb->nlines;
DBG(DEBUG_TAB, fprintf(stderr,
"libmount: %s: %d: SOURCE:%s, MNTPOINT:%s, TYPE:%s, "
"OPTS:%s, FREQ:%d, PASSNO:%d\n",
tb->filename, fs->lineno,
fs->source, fs->target, fs->fstype,
fs->optstr, fs->freq, fs->passno));
return 0;
err:
/* we don't report parse errors to caller; caller has to check
* errors by mnt_tab_get_nerrs() or internaly by MNT_ENTRY_ERR flag
*/
fs->lineno = tb->nlines;
fs->flags |= MNT_FS_ERROR;
return 0;
}
/**
* mnt_tab_parse_file:
* @tb: tab pointer
*
* Parses whole table (e.g. /etc/fstab).
*
* Returns 0 on success and -1 in case of error. The parse errors is possible
* to detect by mnt_tab_get_nerrs() and error message is possible to create by
* mnt_tab_strerror().
*
* Example:
*
* mnt_tab *tb = mnt_new_tab("/etc/fstab");
* int rc;
*
* rc = mnt_tab_parse_file(tb);
* if (rc) {
* if (mnt_tab_get_nerrs(tb)) { / * parse error * /
* mnt_tab_strerror(tb, buf, sizeof(buf));
* fprintf(stderr, "%s: %s\n", progname, buf);
* } else
* perror(mnt_tab_get_name(tb)); / * system error * /
* } else
* mnt_fprintf_tab(tb, stdout, NULL);
*
* mnt_free_tab(tb);
*/
int mnt_tab_parse_file(mnt_tab *tb)
{
FILE *f;
assert(tb);
assert(tb->filename);
if (!tb->filename)
return -1;
f = fopen(tb->filename, "r");
if (!f)
return -1;
while (!feof(f)) {
int rc;
mnt_fs *fs = mnt_new_fs();
if (!fs)
goto error;
rc = mnt_tab_parse_next(tb, f, fs);
if (!rc)
rc = mnt_tab_add_fs(tb, fs);
else if (feof(f)) {
mnt_free_fs(fs);
break;
}
if (rc) {
mnt_free_fs(fs);
goto error;
}
}
fclose(f);
return 0;
error:
fclose(f);
return -1;
}
/**
* mnt_new_tab_parse:
* @filename: /etc/{m,fs}tab or /proc/self/mountinfo path
*
* Same as mnt_new_tab() + mnt_tab_parse_file(). Note that this function does
* not provide details (by mnt_tab_strerror()) about failed parsing -- so you
* should not to use this function for user-writeable files like /etc/fstab.
*
* Returns newly allocated tab on success and NULL in case of error.
*/
mnt_tab *mnt_new_tab_from_file(const char *filename)
{
mnt_tab *tb;
assert(filename);
if (!filename)
return NULL;
tb = mnt_new_tab(filename);
if (tb && mnt_tab_parse_file(tb) != 0) {
mnt_free_tab(tb);
tb = NULL;
}
return tb;
}
/**
* mnt_tab_get_nerrs:
* @tb: pointer to table
*
* Returns number of broken (parse error) entries in the table.
*/
int mnt_tab_get_nerrs(mnt_tab *tb)
{
assert(tb);
return tb->nerrs;
}
/**
* mnt_tab_strerror:
* @tb: pointer to table
* @buf: buffer to return error message
* @buflen: lenght of the buf
*
* Returns error message for table (file) parse errors. For example:
*
* "/etc/fstab: parse error at line(s): 1, 2 and 3."
*/
char *mnt_tab_strerror(mnt_tab *tb, char *buf, size_t buflen)
{
struct list_head *p;
int last = -1;
char *b = buf;
char *end = buf + buflen - 1;
assert(tb);
assert(buf);
assert(buflen);
if (!tb || !tb->nerrs || !buf || buflen <=0)
return NULL;
if (tb->filename) {
snprintf(b, end - b, "%s: ", tb->filename);
b += strnlen(b, end - b);
}
if (tb->nerrs > 1)
strncpy(b, _("parse error at lines: "), end - b);
else
strncpy(b, _("parse error at line: "), end - b);
b += strnlen(b, end - b);
*b = '\0';
list_for_each(p, &tb->ents) {
mnt_fs *fs = list_entry(p, mnt_fs, ents);
if (b == end)
goto done;
if (fs->flags & MNT_FS_ERROR) {
if (last != -1) {
snprintf(b, end - b, "%d, ", last);
b += strnlen(b, end - b);
}
last = fs->lineno;
}
}
if (tb->nerrs == 1)
snprintf(b, end - b, "%d.", last);
else
snprintf(b - 1, end - b, _(" and %d."), last);
done:
return buf;
}
