← Commit list

3eccd7ecb

Denys Vlasenko
Denys Vlasenko
2011-09-22
FAILED Duration: 209s

Subject

mdev: don't reparse rules on -s

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

util-linux/mdev.c +341 -217
util-linux/mdev.c+341 -217
@@ -168,9 +168,29 @@
* This happens regardless of /sys/class/.../dev existence.
*/
+struct rule {
+ bool keep_matching;
+ bool regex_compiled;
+ bool regex_has_slash;
+ mode_t mode;
+ int maj, min0, min1;
+ struct bb_uidgid_t ugid;
+ char *envvar;
+ char *ren_mov;
+ IF_FEATURE_MDEV_EXEC(char *r_cmd;)
+ regex_t match;
+};
+
struct globals {
int root_major, root_minor;
char *subsystem;
+#if ENABLE_FEATURE_MDEV_CONF
+ const char *filename;
+ parser_t *parser;
+ struct rule **rule_vec;
+ unsigned rule_idx;
+#endif
+ struct rule cur_rule;
} FIX_ALIASING;
#define G (*(struct globals*)&bb_common_bufsiz1)
#define INIT_G() do { } while (0)
@@ -182,6 +202,164 @@ struct globals {
/* We use additional 64+ bytes in make_device() */
#define SCRATCH_SIZE 80
+#if 0
+# define dbg(...) bb_error_msg(__VA_ARGS__)
+#else
+# define dbg(...) ((void)0)
+#endif
+
+
+#if ENABLE_FEATURE_MDEV_CONF
+
+static void make_default_cur_rule(void)
+{
+ memset(&G.cur_rule, 0, sizeof(G.cur_rule));
+ G.cur_rule.maj = -1; /* "not a @major,minor rule" */
+ G.cur_rule.mode = 0660;
+}
+
+static void clean_up_cur_rule(void)
+{
+ free(G.cur_rule.envvar);
+ if (G.cur_rule.regex_compiled)
+ regfree(&G.cur_rule.match);
+ free(G.cur_rule.ren_mov);
+ IF_FEATURE_MDEV_EXEC(free(G.cur_rule.r_cmd);)
+ make_default_cur_rule();
+}
+
+static void parse_next_rule(void)
+{
+ /* Note: on entry, G.cur_rule is set to default */
+ while (1) {
+ char *tokens[4];
+ char *val;
+
+ if (!config_read(G.parser, tokens, 4, 3, "# \t", PARSE_NORMAL))
+ break;
+
+ /* Fields: [-]regex uid:gid mode [alias] [cmd] */
+ dbg("token1:'%s'", tokens[1]);
+
+ /* 1st field */
+ val = tokens[0];
+ G.cur_rule.keep_matching = ('-' == val[0]);
+ val += G.cur_rule.keep_matching; /* swallow leading dash */
+ if (val[0] == '@') {
+ /* @major,minor[-minor2] */
+ /* (useful when name is ambiguous:
+ * "/sys/class/usb/lp0" and
+ * "/sys/class/printer/lp0")
+ */
+ int sc = sscanf(val, "@%u,%u-%u", &G.cur_rule.maj, &G.cur_rule.min0, &G.cur_rule.min1);
+ if (sc < 2 || G.cur_rule.maj < 0) {
+ bb_error_msg("bad @maj,min on line %d", G.parser->lineno);
+ goto next_rule;
+ }
+ if (sc == 2)
+ G.cur_rule.min1 = G.cur_rule.min0;
+ } else {
+ if (val[0] == '$') {
+ char *eq = strchr(++val, '=');
+ if (!eq) {
+ bb_error_msg("bad $envvar=regex on line %d", G.parser->lineno);
+ goto next_rule;
+ }
+ G.cur_rule.envvar = xstrndup(val, eq - val);
+ val = eq + 1;
+ }
+ xregcomp(&G.cur_rule.match, val, REG_EXTENDED);
+ G.cur_rule.regex_compiled = 1;
+ G.cur_rule.regex_has_slash = (strchr(val, '/') != NULL);
+ }
+
+ /* 2nd field: uid:gid - device ownership */
+ if (get_uidgid(&G.cur_rule.ugid, tokens[1], /*allow_numeric:*/ 1) == 0) {
+ bb_error_msg("unknown user/group '%s' on line %d", tokens[1], G.parser->lineno);
+ goto next_rule;
+ }
+
+ /* 3rd field: mode - device permissions */
+ bb_parse_mode(tokens[2], &G.cur_rule.mode);
+
+ /* 4th field (opt): ">|=alias" or "!" to not create the node */
+ val = tokens[3];
+ if (ENABLE_FEATURE_MDEV_RENAME && val && strchr(">=!", val[0])) {
+ char *s = skip_non_whitespace(val);
+ G.cur_rule.ren_mov = xstrndup(val, s - val);
+ val = skip_whitespace(s);
+ }
+
+ if (ENABLE_FEATURE_MDEV_EXEC && val && val[0]) {
+ const char *s = "$@*";
+ const char *s2 = strchr(s, val[0]);
+ if (!s2) {
+ bb_error_msg("bad line %u", G.parser->lineno);
+ goto next_rule;
+ }
+ IF_FEATURE_MDEV_EXEC(G.cur_rule.r_cmd = xstrdup(val);)
+ }
+
+ return;
+ next_rule:
+ clean_up_cur_rule();
+ } /* while (config_read) */
+
+ dbg("config_close(G.parser)");
+ config_close(G.parser);
+ G.parser = NULL;
+
+ return;
+}
+
+/* If mdev -s, we remember rules in G.rule_vec[].
+ * Otherwise, there is no point in doing it, and we just
+ * save only one parsed rule in G.cur_rule.
+ */
+static const struct rule *next_rule(void)
+{
+ struct rule *rule;
+
+ /* Open conf file if we didn't do it yet */
+ if (!G.parser && G.filename) {
+ dbg("config_open('%s')", G.filename);
+ G.parser = config_open2(G.filename, fopen_for_read);
+ G.filename = NULL;
+ }
+
+ if (G.rule_vec) {
+ /* mdev -s */
+ /* Do we have rule parsed already? */
+ if (G.rule_vec[G.rule_idx]) {
+ dbg("< G.rule_vec[G.rule_idx:%d]=%p", G.rule_idx, G.rule_vec[G.rule_idx]);
+ return G.rule_vec[G.rule_idx++];
+ }
+ make_default_cur_rule();
+ } else {
+ /* not mdev -s */
+ clean_up_cur_rule();
+ }
+
+ /* Parse one more rule if file isn't fully read */
+ rule = &G.cur_rule;
+ if (G.parser) {
+ parse_next_rule();
+ if (G.rule_vec) { /* mdev -s */
+ rule = memcpy(xmalloc(sizeof(G.cur_rule)), &G.cur_rule, sizeof(G.cur_rule));
+ G.rule_vec = xrealloc_vector(G.rule_vec, 4, G.rule_idx);
+ G.rule_vec[G.rule_idx++] = rule;
+ dbg("> G.rule_vec[G.rule_idx:%d]=%p", G.rule_idx, G.rule_vec[G.rule_idx]);
+ }
+ }
+
+ return rule;
+}
+
+#else
+
+# define next_rule() (&G.cur_rule)
+
+#endif
/* Builds an alias path.
* This function potentionally reallocates the alias parameter.
@@ -218,8 +396,8 @@ static void make_device(char *path, int delete)
{
char *device_name, *subsystem_slash_devname;
int major, minor, type, len;
- mode_t mode;
- parser_t *parser;
+
+ dbg("%s('%s', delete:%d)", __func__, path, delete);
/* 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
@@ -272,246 +450,184 @@ static void make_device(char *path, int delete)
path = subsystem_slash_devname;
}
- /* If we have config file, look up user settings */
- if (ENABLE_FEATURE_MDEV_CONF)
- parser = config_open2("/etc/mdev.conf", fopen_for_read);
-
- do {
- int keep_matching;
- struct bb_uidgid_t ugid;
- char *tokens[4];
- char *command = NULL;
- char *alias = NULL;
+#if ENABLE_FEATURE_MDEV_CONF
+ G.rule_idx = 0; /* restart from the beginning (think mdev -s) */
+#endif
+ for (;;) {
+ const char *str_to_match;
+ regmatch_t off[1 + 9 * ENABLE_FEATURE_MDEV_RENAME_REGEXP];
+ char *command;
+ char *alias;
char aliaslink = aliaslink; /* for compiler */
+ const char *node_name;
+ const struct rule *rule;
- /* Defaults in case we won't match any line */
- ugid.uid = ugid.gid = 0;
- keep_matching = 0;
- mode = 0660;
-
- 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 */
- str_to_match = strchr(val, '/') ? path : device_name;
-
- /* Fields: regex uid:gid mode [alias] [cmd] */
-
- if (val[0] == '@') {
- /* @major,minor[-minor2] */
- /* (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(val, "@%u,%u-%u", &cmaj, &cmin0, &cmin1);
- if (sc < 1
- || major != cmaj
- || (sc == 2 && minor != cmin0)
- || (sc == 3 && (minor < cmin0 || minor > cmin1))
- ) {
- continue; /* this line doesn't match */
- }
- 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 = '=';
+ str_to_match = "";
+
+ rule = next_rule();
+
+#if ENABLE_FEATURE_MDEV_CONF
+ if (rule->maj >= 0) { /* @maj,min rule */
+ if (major != rule->maj)
+ continue;
+ if (minor < rule->min0 || minor > rule->min1)
+ continue;
+ memset(off, 0, sizeof(off));
+ goto rule_matches;
+ }
+ if (rule->envvar) { /* $envvar=regex rule */
+ str_to_match = getenv(rule->envvar);
+ dbg("getenv('%s'):'%s'", rule->envvar, str_to_match);
+ if (!str_to_match)
+ continue;
+ } else {
+ /* regex to match [subsystem/]device_name */
+ str_to_match = (rule->regex_has_slash ? path : device_name);
+ }
+
+ if (rule->regex_compiled) {
+ int regex_match = regexec(&rule->match, str_to_match, ARRAY_SIZE(off), off, 0);
+ dbg("regex_match for '%s':%d", str_to_match, regex_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 (regex_match != 0
+ /* regexec returns whole pattern as "range" 0 */
+ || off[0].rm_so != 0
+ || (int)off[0].rm_eo != (int)strlen(str_to_match)
+ ) {
+ continue; /* this rule doesn't match */
}
- /* else: regex to match [subsystem/]device_name */
-
- {
- regex_t match;
- int result;
-
- xregcomp(&match, val, REG_EXTENDED);
- 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;
- // bb_error_msg("match %d: '%.*s'\n", i,
- // (int)(off[i].rm_eo - off[i].rm_so),
- // device_name + off[i].rm_so);
- //}
-
- /* 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(str_to_match))
- ) {
- continue; /* this line doesn't match */
- }
+ }
+ /* else: it's final implicit "match-all" rule */
+#endif
+
+ rule_matches:
+ dbg("rule matched");
+
+ /* Build alias name */
+ alias = NULL;
+ if (ENABLE_FEATURE_MDEV_RENAME && rule->ren_mov) {
+ aliaslink = rule->ren_mov[0];
+ if (aliaslink == '!') {
+ /* "!": suppress node creation/deletion */
+ major = -2;
}
- line_matches:
- /* This line matches. Stop parsing after parsing
- * the rest the line unless keep_matching == 1 */
-
- /* 2nd field: uid:gid - device ownership */
- if (get_uidgid(&ugid, tokens[1], /*allow_numeric:*/ 1) == 0)
- bb_error_msg("unknown user/group %s on line %d", tokens[1], parser->lineno);
-
- /* 3rd field: mode - device permissions */
- bb_parse_mode(tokens[2], &mode);
-
- val = tokens[3];
- /* 4th field (opt): ">|=alias" or "!" to not create the node */
-
- if (ENABLE_FEATURE_MDEV_RENAME && val) {
- char *a, *s, *st;
-
- a = val;
- s = strchrnul(val, ' ');
- st = strchrnul(val, '\t');
- if (st < s)
- s = st;
- st = (s[0] && s[1]) ? s+1 : NULL;
-
- aliaslink = a[0];
- if (aliaslink == '!' && s == a+1) {
- val = st;
- /* "!": suppress node creation/deletion */
- major = -2;
- }
- else if (aliaslink == '>' || aliaslink == '=') {
- val = st;
- s[0] = '\0';
- if (ENABLE_FEATURE_MDEV_RENAME_REGEXP) {
- char *p;
- unsigned i, n;
-
- /* 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(str_to_match));
- 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, str_to_match + off[i].rm_so, n);
- p += n - 1;
- s++;
- }
+ else if (aliaslink == '>' || aliaslink == '=') {
+ if (ENABLE_FEATURE_MDEV_RENAME_REGEXP) {
+ char *s;
+ char *p;
+ unsigned n;
+
+ /* substitute %1..9 with off[1..9], if any */
+ n = 0;
+ s = rule->ren_mov;
+ while (*s)
+ if (*s++ == '%')
+ n++;
+
+ p = alias = xzalloc(strlen(rule->ren_mov) + n * strlen(str_to_match));
+ s = rule->ren_mov + 1;
+ while (*s) {
+ *p = *s;
+ if ('%' == *s) {
+ unsigned i = (s[1] - '0');
+ if (i <= 9 && off[i].rm_so >= 0) {
+ n = off[i].rm_eo - off[i].rm_so;
+ strncpy(p, str_to_match + off[i].rm_so, n);
+ p += n - 1;
+ s++;
}
- p++;
- s++;
}
- } else {
- alias = xstrdup(a + 1);
+ p++;
+ s++;
}
+ } else {
+ alias = xstrdup(rule->ren_mov + 1);
}
}
+ }
+ dbg("alias:'%s'", alias);
- if (ENABLE_FEATURE_MDEV_EXEC && val) {
- const char *s = "$@*";
- const char *s2 = strchr(s, val[0]);
-
- if (!s2) {
- bb_error_msg("bad line %u", parser->lineno);
- if (ENABLE_FEATURE_MDEV_RENAME)
- free(alias);
- continue;
- }
+ command = NULL;
+ IF_FEATURE_MDEV_EXEC(command = rule->r_cmd;)
+ if (command) {
+ const char *s = "$@*";
+ const char *s2 = strchr(s, command[0]);
- /* Are we running this command now?
- * Run $cmd on delete, @cmd on create, *cmd on both
+ /* Are we running this command now?
+ * Run $cmd on delete, @cmd on create, *cmd on both
+ */
+ if (s2 - s != delete) {
+ /* We are here if: '*',
+ * or: '@' and delete = 0,
+ * or: '$' and delete = 1
*/
- if (s2 - s != delete) {
- /* We are here if: '*',
- * or: '@' and delete = 0,
- * or: '$' and delete = 1
- */
- command = xstrdup(val + 1);
- }
+ command++;
+ } else {
+ command = NULL;
}
}
-
- /* End of field parsing */
+ dbg("command:'%s'", command);
/* "Execute" the line we found */
- {
- const char *node_name;
-
- node_name = device_name;
- if (ENABLE_FEATURE_MDEV_RENAME && alias)
- node_name = alias = build_alias(alias, device_name);
-
- if (!delete && major >= 0) {
- if (mknod(node_name, mode | type, makedev(major, minor)) && errno != EEXIST)
- bb_perror_msg("can't create '%s'", node_name);
- if (major == G.root_major && minor == G.root_minor)
- symlink(node_name, "root");
- if (ENABLE_FEATURE_MDEV_CONF) {
- chmod(node_name, mode);
- chown(node_name, ugid.uid, ugid.gid);
- }
- if (ENABLE_FEATURE_MDEV_RENAME && alias) {
- if (aliaslink == '>')
- symlink(node_name, device_name);
- }
- }
+ node_name = device_name;
+ if (ENABLE_FEATURE_MDEV_RENAME && alias) {
+ node_name = alias = build_alias(alias, device_name);
+ dbg("alias2:'%s'", alias);
+ }
- if (ENABLE_FEATURE_MDEV_EXEC && command) {
- /* setenv will leak memory, use putenv/unsetenv/free */
- char *s = xasprintf("%s=%s", "MDEV", node_name);
- char *s1 = xasprintf("%s=%s", "SUBSYSTEM", G.subsystem);
- putenv(s);
- putenv(s1);
- if (system(command) == -1)
- bb_perror_msg("can't run '%s'", command);
- bb_unsetenv_and_free(s1);
- bb_unsetenv_and_free(s);
- free(command);
+ if (!delete && major >= 0) {
+ dbg("mknod('%s',%o,(%d,%d))", node_name, rule->mode | type, major, minor);
+ if (mknod(node_name, rule->mode | type, makedev(major, minor)) && errno != EEXIST)
+ bb_perror_msg("can't create '%s'", node_name);
+ if (major == G.root_major && minor == G.root_minor)
+ symlink(node_name, "root");
+ if (ENABLE_FEATURE_MDEV_CONF) {
+ chmod(node_name, rule->mode);
+ chown(node_name, rule->ugid.uid, rule->ugid.gid);
}
-
- if (delete && major >= -1) {
- if (ENABLE_FEATURE_MDEV_RENAME && alias) {
- if (aliaslink == '>')
- unlink(device_name);
- }
- unlink(node_name);
+ if (ENABLE_FEATURE_MDEV_RENAME && alias) {
+ if (aliaslink == '>')
+ symlink(node_name, device_name);
}
+ }
- if (ENABLE_FEATURE_MDEV_RENAME)
- free(alias);
+ if (ENABLE_FEATURE_MDEV_EXEC && command) {
+ /* setenv will leak memory, use putenv/unsetenv/free */
+ char *s = xasprintf("%s=%s", "MDEV", node_name);
+ char *s1 = xasprintf("%s=%s", "SUBSYSTEM", G.subsystem);
+ putenv(s);
+ putenv(s1);
+ if (system(command) == -1)
+ bb_perror_msg("can't run '%s'", command);
+ bb_unsetenv_and_free(s1);
+ bb_unsetenv_and_free(s);
}
+ if (delete && major >= -1) {
+ if (ENABLE_FEATURE_MDEV_RENAME && alias) {
+ if (aliaslink == '>')
+ unlink(device_name);
+ }
+ unlink(node_name);
+ }
+
+ if (ENABLE_FEATURE_MDEV_RENAME)
+ free(alias);
+
/* We found matching line.
- * Stop unless it was prefixed with '-' */
- if (ENABLE_FEATURE_MDEV_CONF && !keep_matching)
+ * Stop unless it was prefixed with '-'
+ */
+ if (!ENABLE_FEATURE_MDEV_CONF || !rule->keep_matching)
break;
+ } /* for (;;) */
- /* end of "while line is read from /etc/mdev.conf" */
- } while (ENABLE_FEATURE_MDEV_CONF);
-
- if (ENABLE_FEATURE_MDEV_CONF)
- config_close(parser);
free(subsystem_slash_devname);
}
@@ -618,6 +734,10 @@ int mdev_main(int argc UNUSED_PARAM, char **argv)
INIT_G();
+#if ENABLE_FEATURE_MDEV_CONF
+ G.filename = "/etc/mdev.conf";
+#endif
+
/* We can be called as hotplug helper */
/* Kernel cannot provide suitable stdio fds for us, do it ourself */
bb_sanitize_stdio();
@@ -633,6 +753,10 @@ int mdev_main(int argc UNUSED_PARAM, char **argv)
*/
struct stat st;
+#if ENABLE_FEATURE_MDEV_CONF
+ /* Same as xrealloc_vector(NULL, 4, 0): */
+ G.rule_vec = xzalloc((1 << 4) * sizeof(*G.rule_vec));
+#endif
xstat("/", &st);
G.root_major = major(st.st_dev);
G.root_minor = minor(st.st_dev);