#define root_major (G.root_major)
#define root_minor (G.root_minor)
-#define MAX_SYSFS_DEPTH 3 /* prevent infinite loops in /sys symlinks */
+/* Prevent infinite loops in /sys symlinks */
+#define MAX_SYSFS_DEPTH 3
+
+/* We use additional 64+ bytes in make_device() */
+#define SCRATCH_SIZE 80
+
+static char *next_field(char *s)
+{
+ char *end = skip_non_whitespace(s);
+ s = skip_whitespace(end);
+ *end = '\0';
+ if (*s == '\0')
+ s = NULL;
+ return s;
+}
/* mknod in /dev based on a path like "/sys/block/hda/hda1" */
+/* 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;
int mode = 0660;
uid_t uid = 0;
gid_t gid = 0;
- char *temp = path + strlen(path);
+ char *dev_maj_min = path + strlen(path);
char *command = NULL;
+ char *alias = NULL;
+ char aliaslink = aliaslink; /* for compiler */
+
+ /* 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. We
- * also depend on path having writeable space after it. */
-
+ * also depend on path having writeable space after it.
+ */
if (!delete) {
- strcat(path, "/dev");
- len = open_read_close(path, temp + 1, 64);
- *temp++ = 0;
- if (len < 1) return;
+ strcpy(dev_maj_min, "/dev");
+ len = open_read_close(path, dev_maj_min + 1, 64);
+ *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';
+ }
}
/* Determine device name, type, major and minor */
-
device_name = bb_basename(path);
- type = path[5]=='c' ? S_IFCHR : S_IFBLK;
-
- /* If we have a config file, look up permissions for this device */
+ /* http://kernel.org/doc/pending/hotplug.txt says that only
+ * "/sys/block/..." is for block devices. "/sys/bus" etc is not!
+ * Since kernel 2.6.25 block devices are also in /sys/class/block. */
+ /* TODO: would it be acceptable to just use strstr(path, "/block/")? */
+ if (strncmp(&path[5], "class/block/"+6, 6) != 0
+ && strncmp(&path[5], "class/block/", 12) != 0)
+ type = S_IFCHR;
+ else
+ type = S_IFBLK;
if (ENABLE_FEATURE_MDEV_CONF) {
- char *conf, *pos, *end;
- int line, fd;
+ FILE *fp;
+ char *line, *val, *next;
+ unsigned lineno = 0;
- /* mmap the config file */
- fd = open("/etc/mdev.conf", O_RDONLY);
- if (fd < 0)
- goto end_parse;
- len = xlseek(fd, 0, SEEK_END);
- conf = mmap(NULL, len, PROT_READ, MAP_PRIVATE, fd, 0);
- close(fd);
- if (!conf)
+ /* If we have config file, look up user settings */
+ fp = fopen_or_warn("/etc/mdev.conf", "r");
+ if (!fp)
goto end_parse;
- line = 0;
- /* Loop through lines in mmaped file*/
- for (pos=conf; pos-conf<len;) {
- int field;
- char *end2;
+ while ((line = xmalloc_fgetline(fp)) != NULL) {
+ regmatch_t off[1+9*ENABLE_FEATURE_MDEV_RENAME_REGEXP];
- line++;
- /* find end of this line */
- for (end=pos; end-conf<len && *end!='\n'; end++)
- ;
+ ++lineno;
+ trim(line);
+ if (!line[0])
+ goto next_line;
- /* Three fields: regex, uid:gid, mode */
- for (field=0; field < (3 + ENABLE_FEATURE_MDEV_EXEC);
- field++)
+ /* Fields: regex uid:gid mode [alias] [cmd] */
+
+ /* 1st field: regex to match this device */
+ next = next_field(line);
{
- /* Skip whitespace */
- while (pos<end && isspace(*pos)) pos++;
- if (pos==end || *pos=='#') break;
- for (end2=pos;
- end2<end && !isspace(*end2) && *end2!='#'; end2++)
- ;
-
- if (field == 0) {
- /* Regex to match this device */
-
- char *regex = xstrndup(pos, end2-pos);
- regex_t match;
- regmatch_t off;
- int result;
-
- /* Is this it? */
- xregcomp(&match,regex, REG_EXTENDED);
- result = regexec(&match, device_name, 1, &off, 0);
- regfree(&match);
- free(regex);
-
- /* If not this device, skip rest of line */
- if (result || off.rm_so
- || off.rm_eo != strlen(device_name))
- break;
+ regex_t match;
+ int result;
+
+ /* Is this it? */
+ xregcomp(&match, line, REG_EXTENDED);
+ result = regexec(&match, device_name, 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;
+ // bb_error_msg("match %d: '%.*s'\n", i,
+ // (int)(off[i].rm_eo - off[i].rm_so),
+ // device_name + off[i].rm_so);
+ //}
+
+ /* If not this device, skip rest of line */
+ /* (regexec returns whole pattern as "range" 0) */
+ if (result || off[0].rm_so
+ || ((int)off[0].rm_eo != (int)strlen(device_name))
+ ) {
+ goto next_line;
}
- if (field == 1) {
- /* uid:gid */
-
- char *s, *s2;
-
- /* Find : */
- for (s=pos; s<end2 && *s!=':'; s++)
- ;
- if (s == end2) break;
-
- /* Parse UID */
- uid = strtoul(pos, &s2, 10);
- if (s != s2) {
- struct passwd *pass;
- char *_unam = xstrndup(pos, s-pos);
- pass = getpwnam(_unam);
- free(_unam);
- if (!pass) break;
- uid = pass->pw_uid;
+ }
+
+ /* This line matches: stop parsing the file
+ * after parsing the rest of fields */
+
+ /* 2nd field: uid:gid - device ownership */
+ if (!next) /* field must exist */
+ bb_error_msg_and_die("bad line %u", lineno);
+ val = next;
+ next = next_field(val);
+ {
+ struct passwd *pass;
+ struct group *grp;
+ char *str_uid = val;
+ char *str_gid = strchrnul(val, ':');
+
+ if (*str_gid)
+ *str_gid++ = '\0';
+ /* Parse UID */
+ pass = getpwnam(str_uid);
+ if (pass)
+ uid = pass->pw_uid;
+ else
+ uid = strtoul(str_uid, NULL, 10);
+ /* Parse GID */
+ grp = getgrnam(str_gid);
+ if (grp)
+ gid = grp->gr_gid;
+ else
+ gid = strtoul(str_gid, NULL, 10);
+ }
+
+ /* 3rd field: mode - device permissions */
+ if (!next) /* field must exist */
+ bb_error_msg_and_die("bad line %u", lineno);
+ val = next;
+ next = next_field(val);
+ mode = strtoul(val, NULL, 8);
+
+ /* 4th field (opt): >alias */
+#if ENABLE_FEATURE_MDEV_RENAME
+ if (!next)
+ break;
+ if (*next == '>' || *next == '=') {
+#if ENABLE_FEATURE_MDEV_RENAME_REGEXP
+ char *s, *p;
+ unsigned i, n;
+
+ aliaslink = *next;
+ val = next;
+ next = next_field(val);
+ /* substitute %1..9 with off[1..9], if any */
+ n = 0;
+ s = val;
+ while (*s)
+ if (*s++ == '%')
+ n++;
+
+ p = alias = xzalloc(strlen(val) + n * strlen(device_name));
+ s = val + 1;
+ while (*s) {
+ *p = *s;
+ if ('%' == *s) {
+ i = (s[1] - '0');
+ if (i <= 9 && off[i].rm_so >= 0) {
+ n = off[i].rm_eo - off[i].rm_so;
+ strncpy(p, device_name + off[i].rm_so, n);
+ p += n - 1;
+ s++;
+ }
}
+ p++;
s++;
- /* parse GID */
- gid = strtoul(s, &s2, 10);
- if (end2 != s2) {
- struct group *grp;
- char *_grnam = xstrndup(s, end2-s);
- grp = getgrnam(_grnam);
- free(_grnam);
- if (!grp) break;
- gid = grp->gr_gid;
- }
- }
- if (field == 2) {
- /* mode */
-
- mode = strtoul(pos, &pos, 8);
- if (pos != end2) break;
}
- if (ENABLE_FEATURE_MDEV_EXEC && field == 3) {
- // Command to run
- const char *s = "@$*";
- const char *s2;
- s2 = strchr(s, *pos++);
- if (!s2) {
- // Force error
- field = 1;
- break;
- }
- if ((s2-s+1) & (1<<delete))
- command = xstrndup(pos, end-pos);
+#else
+ aliaslink = *next;
+ val = next;
+ next = next_field(val);
+ alias = xstrdup(val + 1);
+#endif
+ }
+#endif /* ENABLE_FEATURE_MDEV_RENAME */
+
+ /* The rest (opt): command to run */
+ if (!next)
+ break;
+ val = next;
+ if (ENABLE_FEATURE_MDEV_EXEC) {
+ const char *s = "@$*";
+ const char *s2 = strchr(s, *val);
+
+ if (!s2)
+ bb_error_msg_and_die("bad line %u", lineno);
+
+ /* Correlate the position in the "@$*" with the delete
+ * step so that we get the proper behavior:
+ * @cmd: run on create
+ * $cmd: run on delete
+ * *cmd: run on both
+ */
+ if ((s2 - s + 1) /*1/2/3*/ & /*1/2*/ (1 + delete)) {
+ command = xstrdup(val + 1);
}
-
- pos = end2;
}
+ /* end of field parsing */
+ break; /* we found matching line, stop */
+ next_line:
+ free(line);
+ } /* end of "while line is read from /etc/mdev.conf" */
+
+ free(line); /* in case we used "break" to get here */
+ fclose(fp);
+ }
+ end_parse:
- /* Did everything parse happily? */
-
- if (field > 2) break;
- if (field) bb_error_msg_and_die("bad line %d",line);
+ if (!delete && sscanf(dev_maj_min, "%u:%u", &major, &minor) == 2) {
- /* Next line */
- pos = ++end;
- }
- munmap(conf, len);
- end_parse: /* nothing */ ;
- }
+ if (ENABLE_FEATURE_MDEV_RENAME)
+ unlink(device_name);
- umask(0);
- if (!delete) {
- if (sscanf(temp, "%d:%d", &major, &minor) != 2) return;
if (mknod(device_name, mode | type, makedev(major, minor)) && errno != EEXIST)
bb_perror_msg_and_die("mknod %s", device_name);
if (major == root_major && minor == root_minor)
symlink(device_name, "root");
- if (ENABLE_FEATURE_MDEV_CONF) chown(device_name, uid, gid);
+ if (ENABLE_FEATURE_MDEV_CONF) {
+ chown(device_name, uid, gid);
+
+ if (ENABLE_FEATURE_MDEV_RENAME && alias) {
+ char *dest;
+
+ /* ">bar/": rename to bar/device_name */
+ /* ">bar[/]baz": rename to bar[/]baz */
+ dest = strrchr(alias, '/');
+ if (dest) { /* ">bar/[baz]" ? */
+ *dest = '\0'; /* mkdir bar */
+ bb_make_directory(alias, 0755, FILEUTILS_RECUR);
+ *dest = '/';
+ if (dest[1] == '\0') { /* ">bar/" => ">bar/device_name" */
+ dest = alias;
+ alias = concat_path_file(alias, device_name);
+ free(dest);
+ }
+ }
+
+ /* move the device, and optionally
+ * make a symlink to moved device node */
+ if (rename(device_name, alias) == 0 && aliaslink == '>')
+ symlink(alias, device_name);
+
+ free(alias);
+ }
+ }
}
- if (command) {
- /* setenv will leak memory, so use putenv */
+
+ if (ENABLE_FEATURE_MDEV_EXEC && command) {
+ /* setenv will leak memory, use putenv/unsetenv/free */
char *s = xasprintf("MDEV=%s", device_name);
putenv(s);
if (system(command) == -1)
- bb_perror_msg_and_die("cannot run %s", command);
+ bb_perror_msg_and_die("can't run '%s'", command);
s[4] = '\0';
unsetenv(s);
free(s);
free(command);
}
- if (delete) unlink(device_name);
+
+ if (delete)
+ unlink(device_name);
}
/* File callback for /sys/ traversal */
-static int fileAction(const char *fileName, struct stat *statbuf,
- void *userData, int depth)
+static int FAST_FUNC fileAction(const char *fileName,
+ struct stat *statbuf UNUSED_PARAM,
+ void *userData,
+ int depth UNUSED_PARAM)
{
- size_t len = strlen(fileName) - 4;
+ size_t len = strlen(fileName) - 4; /* can't underflow */
char *scratch = userData;
- if (strcmp(fileName + len, "/dev"))
+ /* len check is for paranoid reasons */
+ if (strcmp(fileName + len, "/dev") || len >= PATH_MAX)
return FALSE;
strcpy(scratch, fileName);
- scratch[len] = 0;
+ scratch[len] = '\0';
make_device(scratch, 0);
return TRUE;
}
/* Directory callback for /sys/ traversal */
-static int dirAction(const char *fileName, struct stat *statbuf,
- void *userData, int depth)
+static int FAST_FUNC dirAction(const char *fileName UNUSED_PARAM,
+ struct stat *statbuf UNUSED_PARAM,
+ void *userData UNUSED_PARAM,
+ int depth)
{
return (depth >= MAX_SYSFS_DEPTH ? SKIP : TRUE);
}
int cnt;
int firmware_fd, loading_fd, data_fd;
- /* check for $FIRMWARE from kernel */
- /* XXX: dont bother: open(NULL) works same as open("no-such-file")
- * if (!firmware)
- * return;
- */
-
/* check for /lib/firmware/$FIRMWARE */
xchdir("/lib/firmware");
firmware_fd = xopen(firmware, O_RDONLY);
xchdir(sysfs_path);
for (cnt = 0; cnt < 30; ++cnt) {
loading_fd = open("loading", O_WRONLY);
- if (loading_fd == -1)
- sleep(1);
- else
- break;
+ if (loading_fd != -1)
+ goto loading;
+ sleep(1);
}
- if (loading_fd == -1)
- goto out;
+ goto out;
+ loading:
/* tell kernel we're loading by `echo 1 > /sys/$DEVPATH/loading` */
- if (write(loading_fd, "1", 1) != 1)
+ if (full_write(loading_fd, "1", 1) != 1)
goto out;
/* load firmware by `cat /lib/firmware/$FIRMWARE > /sys/$DEVPATH/data */
/* tell kernel result by `echo [0|-1] > /sys/$DEVPATH/loading` */
if (cnt > 0)
- write(loading_fd, "0", 1);
+ full_write(loading_fd, "0", 1);
else
- write(loading_fd, "-1", 2);
+ full_write(loading_fd, "-1", 2);
out:
if (ENABLE_FEATURE_CLEAN_UP) {
}
}
-int mdev_main(int argc, char **argv);
+int mdev_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int mdev_main(int argc, char **argv)
{
char *action;
char *env_path;
- RESERVE_CONFIG_BUFFER(temp,PATH_MAX);
+ RESERVE_CONFIG_BUFFER(temp, PATH_MAX + SCRATCH_SIZE);
+
+ /* We can be called as hotplug helper */
+ /* Kernel cannot provide suitable stdio fds for us, do it ourself */
+#if 1
+ bb_sanitize_stdio();
+#else
+ /* Debug code */
+ /* Replace LOGFILE by other file or device name if you need */
+#define LOGFILE "/dev/console"
+ /* Just making sure fd 0 is not closed,
+ * we don't really intend to read from it */
+ xmove_fd(xopen("/", O_RDONLY), STDIN_FILENO);
+ xmove_fd(xopen(LOGFILE, O_WRONLY|O_APPEND), STDOUT_FILENO);
+ xmove_fd(xopen(LOGFILE, O_WRONLY|O_APPEND), STDERR_FILENO);
+#endif
xchdir("/dev");
- /* Scan */
-
- if (argc == 2 && !strcmp(argv[1],"-s")) {
+ if (argc == 2 && !strcmp(argv[1], "-s")) {
+ /* Scan:
+ * mdev -s
+ */
struct stat st;
xstat("/", &st);
root_major = major(st.st_dev);
root_minor = minor(st.st_dev);
+ /* ACTION_FOLLOWLINKS is needed since in newer kernels
+ * /sys/block/loop* (for example) are symlinks to dirs,
+ * not real directories.
+ * (kernel's CONFIG_SYSFS_DEPRECATED makes them real dirs,
+ * but we can't enforce that on users) */
recursive_action("/sys/block",
ACTION_RECURSE | ACTION_FOLLOWLINKS,
fileAction, dirAction, temp, 0);
-
recursive_action("/sys/class",
ACTION_RECURSE | ACTION_FOLLOWLINKS,
fileAction, dirAction, temp, 0);
-
- /* Hotplug */
-
} else {
+ /* Hotplug:
+ * env ACTION=... DEVPATH=... mdev
+ * ACTION can be "add" or "remove"
+ * DEVPATH is like "/block/sda" or "/class/input/mice"
+ */
action = getenv("ACTION");
env_path = getenv("DEVPATH");
if (!action || !env_path)
bb_show_usage();
- sprintf(temp, "/sys%s", env_path);
+ snprintf(temp, PATH_MAX, "/sys%s", env_path);
if (!strcmp(action, "remove"))
make_device(temp, 1);
else if (!strcmp(action, "add")) {
make_device(temp, 0);
- if (ENABLE_FEATURE_MDEV_LOAD_FIRMWARE)
- load_firmware(getenv("FIRMWARE"), temp);
+ if (ENABLE_FEATURE_MDEV_LOAD_FIRMWARE) {
+ char *fw = getenv("FIRMWARE");
+ if (fw)
+ load_firmware(fw, temp);
+ }
}
}
- if (ENABLE_FEATURE_CLEAN_UP) RELEASE_CONFIG_BUFFER(temp);
+ if (ENABLE_FEATURE_CLEAN_UP)
+ RELEASE_CONFIG_BUFFER(temp);
+
return 0;
}