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Diffstat (limited to 'util-linux/mdev.c')
-rw-r--r--util-linux/mdev.c208
1 files changed, 99 insertions, 109 deletions
diff --git a/util-linux/mdev.c b/util-linux/mdev.c
index f86ce14..a286605 100644
--- a/util-linux/mdev.c
+++ b/util-linux/mdev.c
@@ -24,6 +24,16 @@ struct globals {
/* 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)
@@ -63,135 +73,115 @@ static void make_device(char *path, int delete)
if (ENABLE_FEATURE_MDEV_CONF) {
FILE *fp;
- char *line, *vline;
+ char *line, *val, *next;
unsigned lineno = 0;
- /* If we have a config file, look up the user settings */
+ /* If we have config file, look up user settings */
fp = fopen_or_warn("/etc/mdev.conf", "r");
if (!fp)
goto end_parse;
- while ((vline = line = xmalloc_fgetline(fp)) != NULL) {
- int field;
- char *orig_line;
-
- if (ENABLE_FEATURE_MDEV_EXEC)
- orig_line = xstrdup(line); /* pristine copy for command execution. */
-
+ while ((line = xmalloc_fgetline(fp)) != NULL) {
++lineno;
-
-// TODO: get rid of loop,
-// just linear skip_whitespace() style code will do!
-// (will also get rid of orig_line).
+ trim(line);
+ if (!line[0])
+ goto next_line;
/* Fields: regex uid:gid mode [alias] [cmd] */
- for (field = 0; field < (3 + ENABLE_FEATURE_MDEV_RENAME + ENABLE_FEATURE_MDEV_EXEC); ++field) {
-
- /* Find a non-empty field */
- char *val;
- do {
- val = strtok(vline, " \t");
- vline = NULL;
- } while (val && !*val);
- if (!val) {
- if (field)
- break;
- else
- goto next_line;
- }
-
- 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 = 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);
-
- } else if (field == 2) {
-
- /* Mode device permissions */
- mode = strtoul(val, NULL, 8);
+ /* 1st field: regex to match this device */
+ next = next_field(line);
+ {
+ regex_t match;
+ regmatch_t off;
+ int result;
+
+ /* Is this it? */
+ xregcomp(&match, line, 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 (ENABLE_FEATURE_MDEV_RENAME && field == 3) {
+ /* This line matches: stop parsing the file
+ * after parsing the rest of fields */
- if (*val != '>')
- ++field;
- else {
- free(alias); /* don't leak in case we matched it on prev line */
- alias = xstrdup(val + 1);
- }
+ /* 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;
+ val = next;
+ next = next_field(val);
+ if (*val == '>') {
+ alias = xstrdup(val + 1);
}
+ }
- if (ENABLE_FEATURE_MDEV_EXEC && field == 3 + ENABLE_FEATURE_MDEV_RENAME) {
-
- /* Optional command to run */
- const char *s = "@$*";
- const char *s2 = strchr(s, *val);
-
- if (!s2) {
- /* Force error */
- field = 1;
- break;
- }
-
- /* Correlate the position in the "@$*" with the delete
- * step so that we get the proper behavior:
- * @cmd: run on create
- * $cmd: run on delete
- * *cmd: run on both
- */
- if ((s2 - s + 1) /*1/2/3*/ & /*1/2*/ (1 + delete)) {
- free(command); /* don't leak in case we matched it on prev line */
- command = xstrdup(orig_line + (val + 1 - line));
- }
+ /* The rest (opt): command to run */
+ if (!next)
+ break;
+ val = next;
+ if (ENABLE_FEATURE_MDEV_EXEC) {
+ const char *s = "@$*";
+ 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);
}
- } /* end of "for every field" */
-
- /* Did everything parse happily? */
- if (field <= 2)
- bb_error_msg_and_die("bad line %u", lineno);
-
+ }
+ /* end of field parsing */
+ break; /* we found matching line, stop */
next_line:
free(line);
- if (ENABLE_FEATURE_MDEV_EXEC)
- free(orig_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: