diff options
Diffstat (limited to 'util-linux/mdev.c')
| -rw-r--r-- | util-linux/mdev.c | 69 |
1 files changed, 42 insertions, 27 deletions
diff --git a/util-linux/mdev.c b/util-linux/mdev.c index a3275f881..ea1edcc40 100644 --- a/util-linux/mdev.c +++ b/util-linux/mdev.c @@ -89,15 +89,11 @@ static char *build_alias(char *alias, const char *device_name) /* NB: "mdev -s" may call us many times, do not leak memory/fds! */ static void make_device(char *path, int delete) { - const char *device_name; + char *device_name; int major, minor, type, len; int mode; - char *dev_maj_min = path + strlen(path); parser_t *parser; - /* Force the configuration file settings exactly. */ - umask(0); - /* Try to read major/minor string. Note that the kernel puts \n after * the data, so we don't need to worry about null terminating the string * because sscanf() will stop at the first nondigit, which \n is. @@ -105,21 +101,23 @@ static void make_device(char *path, int delete) */ major = -1; if (!delete) { + char *dev_maj_min = path + strlen(path); + strcpy(dev_maj_min, "/dev"); len = open_read_close(path, dev_maj_min + 1, 64); - *dev_maj_min++ = '\0'; + *dev_maj_min = '\0'; if (len < 1) { if (!ENABLE_FEATURE_MDEV_EXEC) return; - /* no "dev" file, so just try to run script */ - *dev_maj_min = '\0'; - } else if (sscanf(dev_maj_min, "%u:%u", &major, &minor) != 2) { + /* no "dev" file, but we can still run scripts + * based on device name */ + } else if (sscanf(++dev_maj_min, "%u:%u", &major, &minor) != 2) { major = -1; } } /* Determine device name, type, major and minor */ - device_name = bb_basename(path); + device_name = (char*) bb_basename(path); /* http://kernel.org/doc/pending/hotplug.txt says that only * "/sys/block/..." is for block devices. "/sys/bus" etc is not. * But since 2.6.25 block devices are also in /sys/class/block, @@ -139,9 +137,7 @@ static void make_device(char *path, int delete) parser = config_open2("/etc/mdev.conf", fopen_for_read); do { - regmatch_t off[1 + 9 * ENABLE_FEATURE_MDEV_RENAME_REGEXP]; int keep_matching; - char *val, *name; struct bb_uidgid_t ugid; char *tokens[4]; char *command = NULL; @@ -156,19 +152,22 @@ static void make_device(char *path, int delete) if (ENABLE_FEATURE_MDEV_CONF && config_read(parser, tokens, 4, 3, "# \t", PARSE_NORMAL) ) { + char *val; + char *str_to_match; + regmatch_t off[1 + 9 * ENABLE_FEATURE_MDEV_RENAME_REGEXP]; + val = tokens[0]; keep_matching = ('-' == val[0]); val += keep_matching; /* swallow leading dash */ /* Match against either "subsystem/device_name" * or "device_name" alone */ - name = strchr(val, '/') ? path : (char *) device_name; + str_to_match = strchr(val, '/') ? path : device_name; /* Fields: regex uid:gid mode [alias] [cmd] */ - /* 1st field: @<numeric maj,min>... */ if (val[0] == '@') { - /* @major,minor[-last] */ + /* @major,minor[-minor2] */ /* (useful when name is ambiguous: * "/sys/class/usb/lp0" and * "/sys/class/printer/lp0") */ @@ -182,15 +181,29 @@ static void make_device(char *path, int delete) ) { continue; /* this line doesn't match */ } - } else { /* ... or regex to match device name */ + goto line_matches; + } + if (val[0] == '$') { + /* regex to match an environment variable */ + char *eq = strchr(++val, '='); + if (!eq) + continue; + *eq = '\0'; + str_to_match = getenv(val); + if (!str_to_match) + continue; + str_to_match -= strlen(val) + 1; + *eq = '='; + } + /* else: regex to match [subsystem/]device_name */ + + { regex_t match; int result; - /* Is this it? */ xregcomp(&match, val, REG_EXTENDED); - result = regexec(&match, name, ARRAY_SIZE(off), off, 0); + result = regexec(&match, str_to_match, ARRAY_SIZE(off), off, 0); regfree(&match); - //bb_error_msg("matches:"); //for (int i = 0; i < ARRAY_SIZE(off); i++) { // if (off[i].rm_so < 0) continue; @@ -199,17 +212,17 @@ static void make_device(char *path, int delete) // device_name + off[i].rm_so); //} - /* If not this device, skip rest of line */ + /* If no match, skip rest of line */ /* (regexec returns whole pattern as "range" 0) */ if (result || off[0].rm_so - || ((int)off[0].rm_eo != (int)strlen(name)) + || ((int)off[0].rm_eo != (int)strlen(str_to_match)) ) { continue; /* this line doesn't match */ } } - - /* This line matches: stop parsing the file after parsing - * the rest of fields unless keep_matching == 1 */ + line_matches: + /* This line matches. Stop parsing after parsing + * the rest the line unless keep_matching == 1 */ /* 2nd field: uid:gid - device ownership */ parse_chown_usergroup_or_die(&ugid, tokens[1]); @@ -243,7 +256,7 @@ static void make_device(char *path, int delete) if (*s++ == '%') n++; - p = alias = xzalloc(strlen(a) + n * strlen(name)); + p = alias = xzalloc(strlen(a) + n * strlen(str_to_match)); s = a + 1; while (*s) { *p = *s; @@ -251,7 +264,7 @@ static void make_device(char *path, int delete) i = (s[1] - '0'); if (i <= 9 && off[i].rm_so >= 0) { n = off[i].rm_eo - off[i].rm_so; - strncpy(p, name + off[i].rm_so, n); + strncpy(p, str_to_match + off[i].rm_so, n); p += n - 1; s++; } @@ -447,9 +460,11 @@ int mdev_main(int argc UNUSED_PARAM, char **argv) /* We can be called as hotplug helper */ /* Kernel cannot provide suitable stdio fds for us, do it ourself */ - bb_sanitize_stdio(); + /* Force the configuration file settings exactly */ + umask(0); + xchdir("/dev"); if (argv[1] && strcmp(argv[1], "-s") == 0) { |