diff options
| -rw-r--r-- | modutils/modprobe-small.c | 115 |
1 files changed, 108 insertions, 7 deletions
diff --git a/modutils/modprobe-small.c b/modutils/modprobe-small.c index 1a9d98422..cf9be47a6 100644 --- a/modutils/modprobe-small.c +++ b/modutils/modprobe-small.c @@ -43,6 +43,7 @@ typedef struct module_info { struct globals { module_info *modinfo; char *module_load_options; + smallint dep_bb_seen; int module_count; int module_found_idx; int stringbuf_idx; @@ -51,6 +52,7 @@ struct globals { }; #define G (*ptr_to_globals) #define modinfo (G.modinfo ) +#define dep_bb_seen (G.dep_bb_seen ) #define module_count (G.module_count ) #define module_found_idx (G.module_found_idx ) #define module_load_options (G.module_load_options) @@ -320,13 +322,28 @@ static FAST_FUNC int fileAction(const char *pathname, return TRUE; } -static void load_dep_bb(void) +static int load_dep_bb(void) { char *line; FILE *fp = fopen(DEPFILE_BB, "r"); if (!fp) - return; + return 0; + + dep_bb_seen = 1; + dbg1_error_msg("loading "DEPFILE_BB); + + /* Why? There is a rare scenario: we did not find modprobe.dep.bb, + * we scanned the dir and found no module by name, then we search + * for alias (full scan), and we decided to generate modprobe.dep.bb. + * But we see modprobe.dep.bb.new! Other modprobe is at work! + * We wait and other modprobe renames it to modprobe.dep.bb. + * Now we can use it. + * But we already have modinfo[] filled, and "module_count = 0" + * makes us start anew. Yes, we leak modinfo[].xxx pointers - + * there is not much of data there anyway. */ + module_count = 0; + memset(&modinfo[0], 0, sizeof(modinfo[0])); while ((line = xmalloc_fgetline(fp)) != NULL) { char* space; @@ -355,13 +372,74 @@ static void load_dep_bb(void) free(line); } } + return 1; +} + +static int start_dep_bb_writeout(void) +{ + int fd; + + fd = open(DEPFILE_BB".new", O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 0644); + if (fd < 0) { + if (errno == EEXIST) { + int count = 5 * 20; + dbg1_error_msg(DEPFILE_BB".new exists, waiting for "DEPFILE_BB); + while (1) { + usleep(1000*1000 / 20); + if (load_dep_bb()) { + dbg1_error_msg(DEPFILE_BB" appeared"); + return -2; /* magic number */ + } + if (!--count) + break; + } + bb_error_msg("deleting stale %s", DEPFILE_BB".new"); + fd = open_or_warn(DEPFILE_BB".new", O_WRONLY | O_CREAT | O_TRUNC); + } + } + dbg1_error_msg("opened "DEPFILE_BB".new:%d", fd); + return fd; +} + +static void write_out_dep_bb(int fd) +{ + int i; + FILE *fp; + + /* We want good error reporting. fdprintf is not good enough. */ + fp = fdopen(fd, "w"); + if (!fp) { + close(fd); + goto err; + } + i = 0; + while (modinfo[i].pathname) { + fprintf(fp, "%s%s%s\n" "%s%s\n", + modinfo[i].pathname, modinfo[i].aliases[0] ? " " : "", modinfo[i].aliases, + modinfo[i].deps, modinfo[i].deps[0] ? "\n" : ""); + i++; + } + /* Badly formatted depfile is a no-no. Be paranoid. */ + errno = 0; + if (ferror(fp) | fclose(fp)) + goto err; + if (rename(DEPFILE_BB".new", DEPFILE_BB) != 0) { + err: + bb_perror_msg("can't create %s", DEPFILE_BB); + unlink(DEPFILE_BB".new"); + } else { + dbg1_error_msg("created "DEPFILE_BB); + } } static module_info* find_alias(const char *alias) { int i; + int dep_bb_fd; + module_info *result; dbg1_error_msg("find_alias('%s')", alias); + try_again: /* First try to find by name (cheaper) */ i = 0; while (modinfo[i].pathname) { @@ -376,13 +454,22 @@ static module_info* find_alias(const char *alias) i++; } + /* Ok, we definitely have to scan module bodies. This is a good + * moment to generate modprobe.dep.bb, if it does not exist yet */ + dep_bb_fd = dep_bb_seen ? -1 : start_dep_bb_writeout(); + if (dep_bb_fd == -2) /* modprobe.dep.bb appeared? */ + goto try_again; + /* Scan all module bodies, extract modinfo (it contains aliases) */ i = 0; + result = NULL; while (modinfo[i].pathname) { char *desc, *s; if (!modinfo[i].aliases) { parse_module(&modinfo[i], modinfo[i].pathname); } + if (result) + continue; /* "alias1 symbol:sym1 alias2 symbol:sym2" */ desc = str_2_list(modinfo[i].aliases); /* Does matching substring exist? */ @@ -392,17 +479,25 @@ static module_info* find_alias(const char *alias) * "pci:v000010DEd000000D9sv*sd*bc*sc*i*". * Plain strcmp() won't catch that */ if (fnmatch(s, alias, 0) == 0) { - free(desc); dbg1_error_msg("found alias '%s' in module '%s'", alias, modinfo[i].pathname); - return &modinfo[i]; + result = &modinfo[i]; + break; } } free(desc); + if (result && dep_bb_fd < 0) + return result; i++; } - dbg1_error_msg("find_alias '%s' returns NULL", alias); - return NULL; + + /* Create module.dep.bb if needed */ + if (dep_bb_fd >= 0) { + write_out_dep_bb(dep_bb_fd); + } + + dbg1_error_msg("find_alias '%s' returns %p", alias, result); + return result; } #if ENABLE_FEATURE_MODPROBE_SMALL_CHECK_ALREADY_LOADED @@ -497,7 +592,7 @@ static void process_module(char *name, const char *cmdline_options) /* rmmod? unload it by name */ if (is_rmmod) { - if (delete_module(name, O_NONBLOCK|O_EXCL) != 0 + if (delete_module(name, O_NONBLOCK | O_EXCL) != 0 && !(option_mask32 & OPT_q) ) { bb_perror_msg("remove '%s'", name); @@ -511,6 +606,8 @@ static void process_module(char *name, const char *cmdline_options) } if (!info) { /* both dirscan and find_alias found nothing */ + bb_error_msg("module '%s' not found", name); +//TODO: _and_die()? goto ret; } @@ -637,6 +734,10 @@ int modprobe_main(int argc UNUSED_PARAM, char **argv) argv[1] = NULL; #endif + /* Prevent ugly corner cases with no modules at all */ + modinfo = xzalloc(sizeof(modinfo[0])); + + /* Try to load modprobe.dep.bb */ load_dep_bb(); /* Load/remove modules. |