diff options
Diffstat (limited to 'util-linux')
| -rw-r--r-- | util-linux/mdev.c | 208 |
1 files changed, 99 insertions, 109 deletions
diff --git a/util-linux/mdev.c b/util-linux/mdev.c index f86ce14ce..a2866054c 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: |