#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
+
+#if ENABLE_FEATURE_MDEV_RENAME
+/* Builds an alias path.
+ * This function potentionally reallocates the alias parameter.
+ */
+static char *build_alias(char *alias, const char *device_name)
+{
+ 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);
+ }
+ }
+
+ return alias;
+}
+#endif
/* 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 major, minor, type, len;
int mode = 0660;
- uid_t uid = 0;
- gid_t gid = 0;
- char *temp = path + strlen(path);
+#if ENABLE_FEATURE_MDEV_CONF
+ struct bb_uidgid_t ugid = { 0, 0 };
+ parser_t *parser;
+ char *tokens[5];
+#endif
+#if ENABLE_FEATURE_MDEV_EXEC
char *command = NULL;
+#endif
+#if ENABLE_FEATURE_MDEV_RENAME
+ char *alias = NULL;
+ char aliaslink = aliaslink; /* for compiler */
+#endif
+ char *dev_maj_min = path + strlen(path);
+
+ /* 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.
+ * because sscanf() will stop at the first nondigit, which \n is.
+ * We also depend on path having writeable space after it.
*/
+ major = -1;
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';
+ } 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);
- type = (path[5] == 'c' ? S_IFCHR : S_IFBLK);
-
- if (ENABLE_FEATURE_MDEV_CONF) {
- FILE *fp;
- char *line, *vline;
- size_t lineno = 0;
-
- /* If we have a config file, look up the user settings */
- fp = fopen_or_warn("/etc/mdev.conf", "r");
- if (!fp)
- goto end_parse;
-
- while ((vline = line = xmalloc_getline(fp)) != NULL) {
- int field;
-
- /* A pristine copy for command execution. */
- char *orig_line;
- if (ENABLE_FEATURE_MDEV_EXEC)
- orig_line = xstrdup(line);
-
- ++lineno;
-
- /* Three fields: regex, uid:gid, mode */
- for (field = 0; field < (3 + ENABLE_FEATURE_MDEV_EXEC); ++field) {
-
- /* Find a non-empty field */
- char *val;
- do {
- val = strtok(vline, " \t");
- vline = NULL;
- } while (val && !*val);
- if (!val)
- break;
-
- if (field == 0) {
-
- /* Regex to match this device */
- regex_t match;
- regmatch_t off;
- int result;
-
- /* Is this it? */
- xregcomp(&match, val, REG_EXTENDED);
- result = regexec(&match, device_name, 1, &off, 0);
- regfree(&match);
-
- /* If not this device, skip rest of line */
- if (result || off.rm_so || off.rm_eo != strlen(device_name))
- goto next_line;
-
- } else if (field == 1) {
-
- /* uid:gid device ownership */
- struct passwd *pass;
- struct group *grp;
-
- char *str_uid = val;
- char *str_gid = strchr(val, ':');
- if (str_gid)
- *str_gid = '\0', ++str_gid;
-
- /* 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);
-
- } else if (field == 2) {
+ /* 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.
+ * We use strstr("/block/") to forestall future surprises. */
+ type = S_IFCHR;
+ if (strstr(path, "/block/"))
+ type = S_IFBLK;
+
+#if ENABLE_FEATURE_MDEV_CONF
+ parser = config_open2("/etc/mdev.conf", fopen_for_read);
+
+ /* If we have config file, look up user settings */
+ while (config_read(parser, tokens, 4, 3, "# \t", PARSE_NORMAL)) {
+ regmatch_t off[1 + 9*ENABLE_FEATURE_MDEV_RENAME_REGEXP];
+ char *val;
+
+ /* Fields: regex uid:gid mode [alias] [cmd] */
+
+ /* 1st field: @<numeric maj,min>... */
+ if (tokens[0][0] == '@') {
+ /* @major,minor[-last] */
+ /* (useful when name is ambiguous:
+ * "/sys/class/usb/lp0" and
+ * "/sys/class/printer/lp0") */
+ int cmaj, cmin0, cmin1, sc;
+ if (major < 0)
+ continue; /* no dev, no match */
+ sc = sscanf(tokens[0], "@%u,%u-%u", &cmaj, &cmin0, &cmin1);
+ if (sc < 1 || major != cmaj
+ || (sc == 2 && minor != cmin0)
+ || (sc == 3 && (minor < cmin0 || minor > cmin1))
+ ) {
+ continue; /* no match */
+ }
+ } else { /* ... or regex to match device name */
+ regex_t match;
+ int result;
+
+ /* Is this it? */
+ xregcomp(&match, tokens[0], 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))
+ ) {
+ continue;
+ }
+ }
- /* Mode device permissions */
- mode = strtoul(val, NULL, 8);
+ /* This line matches: stop parsing the file
+ * after parsing the rest of fields */
- } else if (ENABLE_FEATURE_MDEV_EXEC && field == 3) {
+ /* 2nd field: uid:gid - device ownership */
+ parse_chown_usergroup_or_die(&ugid, tokens[1]);
- /* Optional command to run */
- const char *s = "@$*";
- const char *s2 = strchr(s, *val);
+ /* 3rd field: mode - device permissions */
+ mode = strtoul(tokens[2], NULL, 8);
- if (!s2) {
- /* Force error */
- field = 1;
- break;
+ val = tokens[3];
+ /* 4th field (opt): >alias */
+#if ENABLE_FEATURE_MDEV_RENAME
+ if (!val)
+ break;
+ aliaslink = *val;
+ if (aliaslink == '>' || aliaslink == '=') {
+ char *s;
+#if ENABLE_FEATURE_MDEV_RENAME_REGEXP
+ char *p;
+ unsigned i, n;
+#endif
+ char *a = val;
+ s = strchrnul(val, ' ');
+ val = (s[0] && s[1]) ? s+1 : NULL;
+ s[0] = '\0';
+#if ENABLE_FEATURE_MDEV_RENAME_REGEXP
+ /* substitute %1..9 with off[1..9], if any */
+ n = 0;
+ s = a;
+ while (*s)
+ if (*s++ == '%')
+ n++;
+
+ p = alias = xzalloc(strlen(a) + n * strlen(device_name));
+ s = a + 1;
+ while (*s) {
+ *p = *s;
+ if ('%' == *s) {
+ i = (s[1] - '0');
+ if (i <= 9 && off[i].rm_so >= 0) {
+ n = off[i].rm_eo - off[i].rm_so;
+ strncpy(p, device_name + off[i].rm_so, n);
+ p += n - 1;
+ s++;
}
-
- /* Correlate the position in the "@$*" with the delete
- * step so that we get the proper behavior.
- */
- if ((s2 - s + 1) & (1 << delete))
- command = xstrdup(orig_line + (val + 1 - line));
}
+ p++;
+ s++;
}
+#else
+ alias = xstrdup(a + 1);
+#endif
+ }
+#endif /* ENABLE_FEATURE_MDEV_RENAME */
- /* Did everything parse happily? */
- if (field <= 2)
- bb_error_msg_and_die("bad line %i", lineno);
-
- next_line:
- free(line);
- if (ENABLE_FEATURE_MDEV_EXEC)
- free(orig_line);
+#if ENABLE_FEATURE_MDEV_EXEC
+ /* The rest (opt): command to run */
+ if (!val)
+ break;
+ {
+ const char *s = "@$*";
+ const char *s2 = strchr(s, *val);
+
+ if (!s2)
+ bb_error_msg_and_die("bad line %u", parser->lineno);
+
+ /* Correlate the position in the "@$*" 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);
+ }
}
+#endif
+ /* end of field parsing */
+ break; /* we found matching line, stop */
+ } /* end of "while line is read from /etc/mdev.conf" */
- if (ENABLE_FEATURE_CLEAN_UP)
- fclose(fp);
+ config_close(parser);
+#endif /* ENABLE_FEATURE_MDEV_CONF */
- end_parse: /* nothing */ ;
- }
+ if (!delete && major >= 0) {
+
+ 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, ugid.uid, ugid.gid);
+
+#if ENABLE_FEATURE_MDEV_RENAME
+ if (alias) {
+ alias = build_alias(alias, device_name);
+
+ /* 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);
+ }
+#endif
+#endif
}
+
+#if ENABLE_FEATURE_MDEV_EXEC
if (command) {
- /* setenv will leak memory, so use putenv */
+ /* 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);
- s[4] = '\0';
- unsetenv(s);
+ bb_perror_msg_and_die("can't run '%s'", command);
+ unsetenv("MDEV");
free(s);
free(command);
}
- if (delete)
- remove_file(device_name, FILEUTILS_FORCE);
+#endif
+
+ if (delete) {
+ unlink(device_name);
+ /* At creation time, device might have been moved
+ * and a symlink might have been created. Undo that. */
+#if ENABLE_FEATURE_MDEV_RENAME
+ if (alias) {
+ alias = build_alias(alias, device_name);
+ unlink(alias);
+ free(alias);
+ }
+#endif
+ }
}
/* 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") != 0 || 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) MAIN_EXTERNALLY_VISIBLE;
-int mdev_main(int argc, char **argv)
+int mdev_main(int argc UNUSED_PARAM, 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");
- if (argc == 2 && !strcmp(argv[1],"-s")) {
-
+ if (argv[1] && !strcmp(argv[1], "-s")) {
/* Scan:
* mdev -s
*/
-
struct stat st;
xstat("/", &st);
root_major = major(st.st_dev);
root_minor = minor(st.st_dev);
- recursive_action("/sys/block",
- ACTION_RECURSE | ACTION_FOLLOWLINKS,
- fileAction, dirAction, temp, 0);
-
+ /* 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)
+ */
+ if (access("/sys/class/block", F_OK) != 0) {
+ /* Scan obsolete /sys/block only if /sys/class/block
+ * doesn't exist. Otherwise we'll have dupes.
+ */
+ recursive_action("/sys/block",
+ ACTION_RECURSE | ACTION_FOLLOWLINKS,
+ // not needed now? | ACTION_QUIET
+ fileAction, dirAction, temp, 0);
+ }
recursive_action("/sys/class",
ACTION_RECURSE | ACTION_FOLLOWLINKS,
fileAction, dirAction, temp, 0);
-
} else {
+ char *seq;
+ char *action;
+ char *env_path;
+ char seqbuf[sizeof(int)*3 + 2];
+ int seqlen = seqlen; /* for compiler */
/* Hotplug:
- * env ACTION=... DEVPATH=... mdev
+ * env ACTION=... DEVPATH=... [SEQNUM=...] 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);
+ seq = getenv("SEQNUM");
+ if (seq) {
+ int timeout = 2000 / 32;
+ do {
+ seqlen = open_read_close("mdev.seq", seqbuf, sizeof(seqbuf-1));
+ if (seqlen < 0)
+ break;
+ seqbuf[seqlen] = '\0';
+ if (seqbuf[0] == '\n' /* seed file? */
+ || strcmp(seq, seqbuf) == 0 /* correct idx? */
+ ) {
+ break;
+ }
+ usleep(32*1000);
+ } while (--timeout);
+ }
+
+ 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 (seq && seqlen >= 0) {
+ xopen_xwrite_close("mdev.seq", utoa(xatou(seq) + 1));
}
}
projects / oweals / busybox.git / blobdiff