diff options
Diffstat (limited to 'src/librc-depend.c')
| -rw-r--r-- | src/librc-depend.c | 838 |
1 files changed, 838 insertions, 0 deletions
diff --git a/src/librc-depend.c b/src/librc-depend.c new file mode 100644 index 0000000..0da93aa --- /dev/null +++ b/src/librc-depend.c @@ -0,0 +1,838 @@ +/* + librc-depend + rc service dependency and ordering + Copyright 2006-2007 Gentoo Foundation + */ + +#include <sys/types.h> +#include <sys/stat.h> + +#include <err.h> +#include <errno.h> +#include <limits.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "einfo.h" +#include "rc.h" +#include "rc-misc.h" +#include "strlist.h" + +#define GENDEP RC_LIBDIR "/sh/gendepends.sh" + +/* We use this so we can pass our char array through many functions */ +struct lhead +{ + char **list; +}; + +static char *get_shell_value (char *string) +{ + char *p = string; + char *e; + + if (! string) + return (NULL); + + if (*p == '\'') + p++; + + e = p + strlen (p) - 1; + if (*e == '\n') + *e-- = 0; + if (*e == '\'') + *e-- = 0; + + if (*p != 0) + return p; + + return (NULL); +} + +void rc_free_deptree (rc_depinfo_t *deptree) +{ + rc_depinfo_t *di = deptree; + while (di) + { + rc_depinfo_t *dip = di->next; + rc_deptype_t *dt = di->depends; + free (di->service); + while (dt) + { + rc_deptype_t *dtp = dt->next; + free (dt->type); + rc_strlist_free (dt->services); + free (dt); + dt = dtp; + } + free (di); + di = dip; + } +} + +rc_depinfo_t *rc_load_deptree (void) +{ + FILE *fp; + rc_depinfo_t *deptree = NULL; + rc_depinfo_t *depinfo = NULL; + rc_deptype_t *deptype = NULL; + char buffer [RC_LINEBUFFER]; + char *type; + char *p; + char *e; + int i; + + /* Update our deptree, but only if we need too */ + rc_update_deptree (false); + + if (! (fp = fopen (RC_DEPTREE, "r"))) + return (NULL); + + while (fgets (buffer, RC_LINEBUFFER, fp)) + { + p = buffer; + e = strsep (&p, "_"); + if (! e || strcmp (e, "depinfo") != 0) + continue; + + e = strsep (&p, "_"); + if (! e || sscanf (e, "%d", &i) != 1) + continue; + + if (! (type = strsep (&p, "_="))) + continue; + + if (strcmp (type, "service") == 0) + { + /* Sanity */ + e = get_shell_value (p); + if (! e || strlen (e) == 0) + continue; + + if (! deptree) + { + deptree = rc_xmalloc (sizeof (rc_depinfo_t)); + depinfo = deptree; + } + else + { + depinfo->next = rc_xmalloc (sizeof (rc_depinfo_t)); + depinfo = depinfo->next; + } + memset (depinfo, 0, sizeof (rc_depinfo_t)); + depinfo->service = strdup (e); + deptype = NULL; + continue; + } + + e = strsep (&p, "="); + if (! e || sscanf (e, "%d", &i) != 1) + continue; + + /* Sanity */ + e = get_shell_value (p); + if (! e || strlen (e) == 0) + continue; + + if (! deptype) + { + depinfo->depends = rc_xmalloc (sizeof (rc_deptype_t)); + deptype = depinfo->depends; + memset (deptype, 0, sizeof (rc_deptype_t)); + } + else + if (strcmp (deptype->type, type) != 0) + { + deptype->next = rc_xmalloc (sizeof (rc_deptype_t)); + deptype = deptype->next; + memset (deptype, 0, sizeof (rc_deptype_t)); + } + + if (! deptype->type) + deptype->type = strdup (type); + + deptype->services = rc_strlist_addsort (deptype->services, e); + } + fclose (fp); + + return (deptree); +} + +rc_depinfo_t *rc_get_depinfo (rc_depinfo_t *deptree, const char *service) +{ + rc_depinfo_t *di; + + if (! deptree || ! service) + return (NULL); + + for (di = deptree; di; di = di->next) + if (strcmp (di->service, service) == 0) + return (di); + + return (NULL); +} + +rc_deptype_t *rc_get_deptype (rc_depinfo_t *depinfo, const char *type) +{ + rc_deptype_t *dt; + + if (! depinfo || !type) + return (NULL); + + for (dt = depinfo->depends; dt; dt = dt->next) + if (strcmp (dt->type, type) == 0) + return (dt); + + return (NULL); +} + +static bool valid_service (const char *runlevel, const char *service) +{ + return ((strcmp (runlevel, RC_LEVEL_BOOT) != 0 && + rc_service_in_runlevel (service, RC_LEVEL_BOOT)) || + rc_service_in_runlevel (service, runlevel) || + rc_service_state (service, rc_service_coldplugged) || + rc_service_state (service, rc_service_started)); +} + +static bool get_provided1 (const char *runlevel, struct lhead *providers, + rc_deptype_t *deptype, + const char *level, bool coldplugged, + bool started, bool inactive) +{ + char *service; + int i; + bool retval = false; + + STRLIST_FOREACH (deptype->services, service, i) + { + bool ok = true; + if (level) + ok = rc_service_in_runlevel (service, level); + else if (coldplugged) + ok = (rc_service_state (service, rc_service_coldplugged) && + ! rc_service_in_runlevel (service, runlevel) && + ! rc_service_in_runlevel (service, RC_LEVEL_BOOT)); + + if (! ok) + continue; + + if (started) + ok = (rc_service_state (service, rc_service_starting) || + rc_service_state (service, rc_service_started) || + rc_service_state (service, rc_service_stopping)); + else if (inactive) + ok = rc_service_state (service, rc_service_inactive); + + if (! ok) + continue; + + retval = true; + providers->list = rc_strlist_add (providers->list, service); + } + + return (retval); +} + +/* Work out if a service is provided by another service. + For example metalog provides logger. + We need to be able to handle syslogd providing logger too. + We do this by checking whats running, then what's starting/stopping, + then what's run in the runlevels and finally alphabetical order. + + If there are any bugs in rc-depend, they will probably be here as + provided dependancy can change depending on runlevel state. + */ +static char **get_provided (rc_depinfo_t *deptree, rc_depinfo_t *depinfo, + const char *runlevel, int options) +{ + rc_deptype_t *dt; + struct lhead providers; + char *service; + int i; + + if (! deptree || ! depinfo) + return (NULL); + if (rc_service_exists (depinfo->service)) + return (NULL); + + dt = rc_get_deptype (depinfo, "providedby"); + if (! dt) + return (NULL); + + memset (&providers, 0, sizeof (struct lhead)); + /* If we are stopping then all depends are true, regardless of state. + This is especially true for net services as they could force a restart + of the local dns resolver which may depend on net. */ + if (options & RC_DEP_STOP) + { + STRLIST_FOREACH (dt->services, service, i) + providers.list = rc_strlist_add (providers.list, service); + + return (providers.list); + } + + /* If we're strict, then only use what we have in our runlevel */ + if (options & RC_DEP_STRICT) + { + STRLIST_FOREACH (dt->services, service, i) + if (rc_service_in_runlevel (service, runlevel)) + providers.list = rc_strlist_add (providers.list, service); + + if (providers.list) + return (providers.list); + } + + /* OK, we're not strict or there were no services in our runlevel. + This is now where the logic gets a little fuzzy :) + If there is >1 running service then we return NULL. + We do this so we don't hang around waiting for inactive services and + our need has already been satisfied as it's not strict. + We apply this to our runlevel, coldplugged services, then bootlevel + and finally any running.*/ +#define DO \ + if (providers.list && providers.list[0] && providers.list[1]) \ + { \ + rc_strlist_free (providers.list); \ + return (NULL); \ + } \ + else if (providers.list) \ + return providers.list; \ + + /* Anything in the runlevel has to come first */ + if (get_provided1 (runlevel, &providers, dt, runlevel, false, true, false)) + { DO } + if (get_provided1 (runlevel, &providers, dt, runlevel, false, false, true)) + { DO } + if (get_provided1 (runlevel, &providers, dt, runlevel, false, false, false)) + return (providers.list); + + /* Check coldplugged started services */ + if (get_provided1 (runlevel, &providers, dt, NULL, true, true, false)) + { DO } + + /* Check bootlevel if we're not in it */ + if (strcmp (runlevel, RC_LEVEL_BOOT) != 0) + { + if (get_provided1 (runlevel, &providers, dt, RC_LEVEL_BOOT, false, true, false)) + { DO } + if (get_provided1 (runlevel, &providers, dt, RC_LEVEL_BOOT, false, false, true)) + { DO } + } + + /* Check coldplugged inactive services */ + if (get_provided1 (runlevel, &providers, dt, NULL, true, false, true)) + { DO } + + /* Check manually started */ + if (get_provided1 (runlevel, &providers, dt, NULL, false, true, false)) + { DO } + if (get_provided1 (runlevel, &providers, dt, NULL, false, false, true)) + { DO } + + /* Nothing started then. OK, lets get the stopped services */ + if (get_provided1 (runlevel, &providers, dt, NULL, true, false, false)) + return (providers.list); + if ((strcmp (runlevel, RC_LEVEL_BOOT) != 0) + && (get_provided1 (runlevel, &providers, dt, RC_LEVEL_BOOT, false, false, false))) + return (providers.list); + + /* Still nothing? OK, list all services */ + STRLIST_FOREACH (dt->services, service, i) + providers.list = rc_strlist_add (providers.list, service); + + return (providers.list); +} + +static void visit_service (rc_depinfo_t *deptree, char **types, + struct lhead *sorted, struct lhead *visited, + rc_depinfo_t *depinfo, + const char *runlevel, int options) +{ + int i, j, k; + char *lp, *item; + char *service; + rc_depinfo_t *di; + rc_deptype_t *dt; + char **provides; + char *svcname; + + if (! deptree || !sorted || !visited || !depinfo) + return; + + /* Check if we have already visited this service or not */ + STRLIST_FOREACH (visited->list, item, i) + if (strcmp (item, depinfo->service) == 0) + return; + + /* Add ourselves as a visited service */ + visited->list = rc_strlist_add (visited->list, depinfo->service); + + STRLIST_FOREACH (types, item, i) + { + if ((dt = rc_get_deptype (depinfo, item))) + { + STRLIST_FOREACH (dt->services, service, j) + { + if (! options & RC_DEP_TRACE || strcmp (item, "iprovide") == 0) + { + sorted->list = rc_strlist_add (sorted->list, service); + continue; + } + + di = rc_get_depinfo (deptree, service); + if ((provides = get_provided (deptree, di, runlevel, options))) + { + STRLIST_FOREACH (provides, lp, k) + { + di = rc_get_depinfo (deptree, lp); + if (di && (strcmp (item, "ineed") == 0 || + valid_service (runlevel, di->service))) + visit_service (deptree, types, sorted, visited, di, + runlevel, options | RC_DEP_TRACE); + } + rc_strlist_free (provides); + } + else + if (di && (strcmp (item, "ineed") == 0 || + valid_service (runlevel, service))) + visit_service (deptree, types, sorted, visited, di, + runlevel, options | RC_DEP_TRACE); + } + } + } + + /* Now visit the stuff we provide for */ + if (options & RC_DEP_TRACE && (dt = rc_get_deptype (depinfo, "iprovide"))) + { + STRLIST_FOREACH (dt->services, service, i) + { + if ((di = rc_get_depinfo (deptree, service))) + if ((provides = get_provided (deptree, di, runlevel, options))) + { + STRLIST_FOREACH (provides, lp, j) + if (strcmp (lp, depinfo->service) == 0) + { + visit_service (deptree, types, sorted, visited, di, + runlevel, options | RC_DEP_TRACE); + break; + } + rc_strlist_free (provides); + } + } + } + + /* We've visited everything we need, so add ourselves unless we + are also the service calling us or we are provided by something */ + svcname = getenv("SVCNAME"); + if (! svcname || strcmp (svcname, depinfo->service) != 0) + if (! rc_get_deptype (depinfo, "providedby")) + sorted->list = rc_strlist_add (sorted->list, depinfo->service); +} + +char **rc_get_depends (rc_depinfo_t *deptree, + char **types, char **services, + const char *runlevel, int options) +{ + struct lhead sorted; + struct lhead visited; + rc_depinfo_t *di; + char *service; + int i; + + if (! deptree || ! types || ! services) + return (NULL); + + memset (&sorted, 0, sizeof (struct lhead)); + memset (&visited, 0, sizeof (struct lhead)); + + STRLIST_FOREACH (services, service, i) + { + di = rc_get_depinfo (deptree, service); + visit_service (deptree, types, &sorted, &visited, di, runlevel, options); + } + + rc_strlist_free (visited.list); + return (sorted.list); +} + +char **rc_order_services (rc_depinfo_t *deptree, const char *runlevel, + int options) +{ + char **list = NULL; + char **types = NULL; + char **services = NULL; + bool reverse = false; + + if (! runlevel) + return (NULL); + + /* When shutting down, list all running services */ + if (strcmp (runlevel, RC_LEVEL_SINGLE) == 0 || + strcmp (runlevel, RC_LEVEL_SHUTDOWN) == 0 || + strcmp (runlevel, RC_LEVEL_REBOOT) == 0) + { + list = rc_ls_dir (list, RC_SVCDIR_STARTING, RC_LS_INITD); + list = rc_ls_dir (list, RC_SVCDIR_INACTIVE, RC_LS_INITD); + list = rc_ls_dir (list, RC_SVCDIR_STARTED, RC_LS_INITD); + reverse = true; + } + else + { + list = rc_services_in_runlevel (runlevel); + + /* Add coldplugged services */ + list = rc_ls_dir (list, RC_SVCDIR_COLDPLUGGED, RC_LS_INITD); + + /* If we're not the boot runlevel then add that too */ + if (strcmp (runlevel, RC_LEVEL_BOOT) != 0) + { + char *path = rc_strcatpaths (RC_RUNLEVELDIR, RC_LEVEL_BOOT, NULL); + list = rc_ls_dir (list, path, RC_LS_INITD); + free (path); + } + } + + /* Now we have our lists, we need to pull in any dependencies + and order them */ + types = rc_strlist_add (NULL, "ineed"); + types = rc_strlist_add (types, "iuse"); + types = rc_strlist_add (types, "iafter"); + services = rc_get_depends (deptree, types, list, runlevel, + RC_DEP_STRICT | RC_DEP_TRACE | options); + rc_strlist_free (list); + rc_strlist_free (types); + + if (reverse) + rc_strlist_reverse (services); + + return (services); +} + +static bool is_newer_than (const char *file, const char *target) +{ + struct stat buf; + int mtime; + + if (stat (file, &buf) != 0 || buf.st_size == 0) + return (false); + mtime = buf.st_mtime; + + if (stat (target, &buf) != 0) + return (false); + + if (mtime < buf.st_mtime) + return (false); + + if (rc_is_dir (target)) + { + char **targets = rc_ls_dir (NULL, target, 0); + char *t; + int i; + bool newer = true; + STRLIST_FOREACH (targets, t, i) + { + char *path = rc_strcatpaths (target, t, NULL); + newer = is_newer_than (file, path); + free (path); + if (! newer) + break; + } + rc_strlist_free (targets); + return (newer); + } + + return (true); +} + +typedef struct deppair +{ + const char *depend; + const char *addto; +} deppair_t; + +static const deppair_t deppairs[] = { + { "ineed", "needsme" }, + { "iuse", "usesme" }, + { "iafter", "ibefore" }, + { "ibefore", "iafter" }, + { "iprovide", "providedby" }, + { NULL, NULL } +}; + +static const char *depdirs[] = +{ + RC_SVCDIR "starting", + RC_SVCDIR "started", + RC_SVCDIR "stopping", + RC_SVCDIR "inactive", + RC_SVCDIR "wasinactive", + RC_SVCDIR "failed", + RC_SVCDIR "coldplugged", + RC_SVCDIR "daemons", + RC_SVCDIR "options", + RC_SVCDIR "exclusive", + RC_SVCDIR "scheduled", + RC_SVCDIR "ebuffer", + NULL +}; + +/* This is a 5 phase operation + Phase 1 is a shell script which loads each init script and config in turn + and echos their dependency info to stdout + Phase 2 takes that and populates a depinfo object with that data + Phase 3 adds any provided services to the depinfo object + Phase 4 scans that depinfo object and puts in backlinks + Phase 5 saves the depinfo object to disk + */ +int rc_update_deptree (bool force) +{ + char *depends; + char *service; + char *type; + char *depend; + int retval = 0; + FILE *fp; + rc_depinfo_t *deptree; + rc_depinfo_t *depinfo; + rc_depinfo_t *di; + rc_depinfo_t *last_depinfo = NULL; + rc_deptype_t *deptype; + rc_deptype_t *dt; + rc_deptype_t *last_deptype = NULL; + char buffer[RC_LINEBUFFER]; + int len; + int i; + int j; + int k; + bool already_added; + + /* Create base directories if needed */ + for (i = 0; depdirs[i]; i++) + if (! rc_is_dir (depdirs[i])) + if (mkdir (depdirs[i], 0755) != 0) + eerrorx ("mkdir `%s': %s", depdirs[i], strerror (errno)); + + if (! force) + if (is_newer_than (RC_DEPTREE, RC_INITDIR) && + is_newer_than (RC_DEPTREE, RC_CONFDIR) && + is_newer_than (RC_DEPTREE, "/etc/rc.conf")) + return 0; + + ebegin ("Caching service dependencies"); + + /* Some init scripts need RC_LIBDIR to source stuff + Ideally we should be setting our full env instead */ + if (! getenv ("RC_LIBDIR")) + setenv ("RC_LIBDIR", RC_LIBDIR, 0); + + /* Phase 1 */ + if ((fp = popen (GENDEP, "r")) == NULL) + eerrorx ("popen: %s", strerror (errno)); + + deptree = rc_xmalloc (sizeof (rc_depinfo_t)); + memset (deptree, 0, sizeof (rc_depinfo_t)); + memset (buffer, 0, RC_LINEBUFFER); + + /* Phase 2 */ + while (fgets (buffer, RC_LINEBUFFER, fp)) + { + /* Trim the newline */ + if (buffer[strlen (buffer) - 1] == '\n') + buffer[strlen(buffer) -1] = 0; + + depends = buffer; + service = strsep (&depends, " "); + if (! service) + continue; + type = strsep (&depends, " "); + + for (depinfo = deptree; depinfo; depinfo = depinfo->next) + { + last_depinfo = depinfo; + if (depinfo->service && strcmp (depinfo->service, service) == 0) + break; + } + + if (! depinfo) + { + if (! last_depinfo->service) + depinfo = last_depinfo; + else + { + last_depinfo->next = rc_xmalloc (sizeof (rc_depinfo_t)); + depinfo = last_depinfo->next; + } + memset (depinfo, 0, sizeof (rc_depinfo_t)); + depinfo->service = strdup (service); + } + + /* We may not have any depends */ + if (! type || ! depends) + continue; + + last_deptype = NULL; + for (deptype = depinfo->depends; deptype; deptype = deptype->next) + { + last_deptype = deptype; + if (strcmp (deptype->type, type) == 0) + break; + } + + if (! deptype) + { + if (! last_deptype) + { + depinfo->depends = rc_xmalloc (sizeof (rc_deptype_t)); + deptype = depinfo->depends; + } + else + { + last_deptype->next = rc_xmalloc (sizeof (rc_deptype_t)); + deptype = last_deptype->next; + } + memset (deptype, 0, sizeof (rc_deptype_t)); + deptype->type = strdup (type); + } + + /* Now add each depend to our type. + We do this individually so we handle multiple spaces gracefully */ + while ((depend = strsep (&depends, " "))) + { + if (depend[0] == 0) + continue; + + /* .sh files are not init scripts */ + len = strlen (depend); + if (len > 2 && + depend[len - 3] == '.' && + depend[len - 2] == 's' && + depend[len - 1] == 'h') + continue; + + deptype->services = rc_strlist_addsort (deptype->services, depend); + } + + } + pclose (fp); + + /* Phase 3 - add our providors to the tree */ + for (depinfo = deptree; depinfo; depinfo = depinfo->next) + { + if ((deptype = rc_get_deptype (depinfo, "iprovide"))) + STRLIST_FOREACH (deptype->services, service, i) + { + for (di = deptree; di; di = di->next) + { + last_depinfo = di; + if (strcmp (di->service, service) == 0) + break; + } + if (! di) + { + last_depinfo->next = rc_xmalloc (sizeof (rc_depinfo_t)); + di = last_depinfo->next; + memset (di, 0, sizeof (rc_depinfo_t)); + di->service = strdup (service); + } + } + } + + /* Phase 4 - backreference our depends */ + for (depinfo = deptree; depinfo; depinfo = depinfo->next) + { + for (i = 0; deppairs[i].depend; i++) + { + deptype = rc_get_deptype (depinfo, deppairs[i].depend); + if (! deptype) + continue; + + STRLIST_FOREACH (deptype->services, service, j) + { + di = rc_get_depinfo (deptree, service); + if (! di) + { + if (strcmp (deptype->type, "ineed") == 0) + { + eerror ("Service `%s' needs non existant service `%s'", + depinfo->service, service); + retval = -1; + } + continue; + } + + /* Add our deptype now */ + last_deptype = NULL; + for (dt = di->depends; dt; dt = dt->next) + { + last_deptype = dt; + if (strcmp (dt->type, deppairs[i].addto) == 0) + break; + } + if (! dt) + { + if (! last_deptype) + { + di->depends = rc_xmalloc (sizeof (rc_deptype_t)); + dt = di->depends; + } + else + { + last_deptype->next = rc_xmalloc (sizeof (rc_deptype_t)); + dt = last_deptype->next; + } + memset (dt, 0, sizeof (rc_deptype_t)); + dt->type = strdup (deppairs[i].addto); + } + + already_added = false; + STRLIST_FOREACH (dt->services, service, k) + if (strcmp (service, depinfo->service) == 0) + { + already_added = true; + break; + } + + if (! already_added) + dt->services = rc_strlist_addsort (dt->services, + depinfo->service); + } + } + } + + /* Phase 5 - save to disk + Now that we're purely in C, do we need to keep a shell parseable file? + I think yes as then it stays human readable + This works and should be entirely shell parseable provided that depend + names don't have any non shell variable characters in + */ + if ((fp = fopen (RC_DEPTREE, "w")) == NULL) + eerror ("fopen `%s': %s", RC_DEPTREE, strerror (errno)); + else + { + i = 0; + for (depinfo = deptree; depinfo; depinfo = depinfo->next) + { + fprintf (fp, "depinfo_%d_service='%s'\n", i, depinfo->service); + for (deptype = depinfo->depends; deptype; deptype = deptype->next) + { + k = 0; + STRLIST_FOREACH (deptype->services, service, j) + { + fprintf (fp, "depinfo_%d_%s_%d='%s'\n", i, deptype->type, + k, service); + k++; + } + } + i++; + } + fclose (fp); + } + + rc_free_deptree (deptree); + + eend (retval, "Failed to update the service dependency tree"); + return (retval); +} |