From 40b97fb31ec7c24db706b47182f400f2a13dbbfc Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Tue, 26 Feb 2013 00:40:46 +0100 Subject: [PATCH] mdev: add environment variable match function old new delta make_device 1998 2189 +191 clean_up_cur_rule 61 96 +35 dirAction 75 87 +12 mdev_main 838 849 +11 packed_usage 29272 29273 +1 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 5/0 up/down: 250/0) Total: 250 bytes Signed-off-by: Denys Vlasenko --- docs/mdev.txt | 4 +-- util-linux/mdev.c | 77 +++++++++++++++++++++++++++++++++++++++++++---- 2 files changed, 73 insertions(+), 8 deletions(-) diff --git a/docs/mdev.txt b/docs/mdev.txt index 61f93c9df..b24025f7b 100644 --- a/docs/mdev.txt +++ b/docs/mdev.txt @@ -51,9 +51,9 @@ device nodes if your system needs something more than the default root/root 660 permissions. The file has the format: - [-] : + [-][envmatch] : or - @ : + [envmatch]@ : or $envvar= : diff --git a/util-linux/mdev.c b/util-linux/mdev.c index c592ef687..775e5c241 100644 --- a/util-linux/mdev.c +++ b/util-linux/mdev.c @@ -80,7 +80,7 @@ //usage: IF_FEATURE_MDEV_CONF( //usage: "\n" //usage: "It uses /etc/mdev.conf with lines\n" -//usage: " [-]DEVNAME UID:GID PERM" +//usage: " [-][ENV=regex;]...DEVNAME UID:GID PERM" //usage: IF_FEATURE_MDEV_RENAME(" [>|=PATH]|[!]") //usage: IF_FEATURE_MDEV_EXEC(" [@|$|*PROG]") //usage: "\n" @@ -233,6 +233,12 @@ static const char keywords[] ALIGN1 = "add\0remove\0change\0"; enum { OP_add, OP_remove }; +struct envmatch { + struct envmatch *next; + char *envname; + regex_t match; +}; + struct rule { bool keep_matching; bool regex_compiled; @@ -243,6 +249,7 @@ struct rule { char *ren_mov; IF_FEATURE_MDEV_EXEC(char *r_cmd;) regex_t match; + struct envmatch *envmatch; }; struct globals { @@ -288,14 +295,48 @@ static void make_default_cur_rule(void) static void clean_up_cur_rule(void) { + struct envmatch *e; + free(G.cur_rule.envvar); + free(G.cur_rule.ren_mov); 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);) + e = G.cur_rule.envmatch; + while (e) { + free(e->envname); + regfree(&e->match); + e = e->next; + } make_default_cur_rule(); } +static char *parse_envmatch_pfx(char *val) +{ + struct envmatch **nextp = &G.cur_rule.envmatch; + + for (;;) { + struct envmatch *e; + char *semicolon; + char *eq = strchr(val, '='); + if (!eq /* || eq == val? */) + return val; + if (endofname(val) != eq) + return val; + semicolon = strchr(eq, ';'); + if (!semicolon) + return val; + /* ENVVAR=regex;... */ + *nextp = e = xzalloc(sizeof(*e)); + nextp = &e->next; + e->envname = xstrndup(val, eq - val); + *semicolon = '\0'; + xregcomp(&e->match, eq + 1, REG_EXTENDED); + *semicolon = ';'; + val = semicolon + 1; + } +} + static void parse_next_rule(void) { /* Note: on entry, G.cur_rule is set to default */ @@ -314,6 +355,7 @@ static void parse_next_rule(void) val = tokens[0]; G.cur_rule.keep_matching = ('-' == val[0]); val += G.cur_rule.keep_matching; /* swallow leading dash */ + val = parse_envmatch_pfx(val); if (val[0] == '@') { /* @major,minor[-minor2] */ /* (useful when name is ambiguous: @@ -328,8 +370,10 @@ static void parse_next_rule(void) if (sc == 2) G.cur_rule.min1 = G.cur_rule.min0; } else { + char *eq = strchr(val, '='); if (val[0] == '$') { - char *eq = strchr(++val, '='); + /* $ENVVAR=regex ... */ + val++; if (!eq) { bb_error_msg("bad $envvar=regex on line %d", G.parser->lineno); goto next_rule; @@ -423,6 +467,21 @@ static const struct rule *next_rule(void) return rule; } +static int env_matches(struct envmatch *e) +{ + while (e) { + int r; + char *val = getenv(e->envname); + if (!val) + return 0; + r = regexec(&e->match, val, /*size*/ 0, /*range[]*/ NULL, /*eflags*/ 0); + if (r != 0) /* no match */ + return 0; + e = e->next; + } + return 1; +} + #else # define next_rule() (&G.cur_rule) @@ -537,6 +596,8 @@ static void make_device(char *device_name, char *path, int operation) rule = next_rule(); #if ENABLE_FEATURE_MDEV_CONF + if (!env_matches(rule->envmatch)) + continue; if (rule->maj >= 0) { /* @maj,min rule */ if (major != rule->maj) continue; @@ -749,8 +810,10 @@ static int FAST_FUNC dirAction(const char *fileName UNUSED_PARAM, if (1 == depth) { free(G.subsystem); G.subsystem = strrchr(fileName, '/'); - if (G.subsystem) + if (G.subsystem) { G.subsystem = xstrdup(G.subsystem + 1); + xsetenv("SUBSYSTEM", G.subsystem); + } } return (depth >= MAX_SYSFS_DEPTH ? SKIP : TRUE); @@ -843,8 +906,8 @@ int mdev_main(int argc UNUSED_PARAM, char **argv) xchdir("/dev"); if (argv[1] && strcmp(argv[1], "-s") == 0) { - /* Scan: - * mdev -s + /* + * Scan: mdev -s */ struct stat st; @@ -856,6 +919,8 @@ int mdev_main(int argc UNUSED_PARAM, char **argv) G.root_major = major(st.st_dev); G.root_minor = minor(st.st_dev); + putenv((char*)"ACTION=add"); + /* ACTION_FOLLOWLINKS is needed since in newer kernels * /sys/block/loop* (for example) are symlinks to dirs, * not real directories. -- 2.25.1