From 1f72ed3900db6b43ecbde097c83c4c5ddf9c9e38 Mon Sep 17 00:00:00 2001 From: Laurent Bercot Date: Mon, 4 Dec 2017 14:59:44 +0000 Subject: Refactor s6-rc-init and s6-rc-upgrade around atomic_symlink and s6rc_livedir_create --- src/include/s6-rc/s6rc-utils.h | 1 + src/libs6rc/deps-lib/s6rc | 1 + src/libs6rc/s6rc_livedir_create.c | 50 ++++++++++ src/s6-rc/s6-rc-init.c | 190 +++++++++++--------------------------- src/s6-rc/s6-rc-update.c | 118 ++++++++--------------- 5 files changed, 144 insertions(+), 216 deletions(-) create mode 100644 src/libs6rc/s6rc_livedir_create.c (limited to 'src') diff --git a/src/include/s6-rc/s6rc-utils.h b/src/include/s6-rc/s6rc-utils.h index b6cab0a..8f67920 100644 --- a/src/include/s6-rc/s6rc-utils.h +++ b/src/include/s6-rc/s6rc-utils.h @@ -14,5 +14,6 @@ extern int s6rc_sanitize_dir (stralloc *, char const *, size_t *) ; extern int s6rc_livedir_prefixsize (char const *, size_t *) ; extern ssize_t s6rc_livedir_prefix (char const *, char *, size_t) ; +extern int s6rc_livedir_create (stralloc *, char const *, char const *, char const *, char const *, char const *, unsigned char const *, unsigned int, size_t *) ; #endif diff --git a/src/libs6rc/deps-lib/s6rc b/src/libs6rc/deps-lib/s6rc index f42783b..52c220f 100644 --- a/src/libs6rc/deps-lib/s6rc +++ b/src/libs6rc/deps-lib/s6rc @@ -5,6 +5,7 @@ s6rc_db_read.o s6rc_db_read_sizes.o s6rc_db_read_uint32.o s6rc_graph_closure.o +s6rc_livedir_create.o s6rc_livedir_prefix.o s6rc_livedir_prefixsize.o s6rc_lock.o diff --git a/src/libs6rc/s6rc_livedir_create.c b/src/libs6rc/s6rc_livedir_create.c new file mode 100644 index 0000000..1da0ac3 --- /dev/null +++ b/src/libs6rc/s6rc_livedir_create.c @@ -0,0 +1,50 @@ +/* ISC license. */ + +#include +#include +#include +#include +#include /* mkdtemp */ +#include +#include +#include + +int s6rc_livedir_create (stralloc *sa, char const *live, char const *suffix, char const *scandir, char const *prefix, char const *compiled, unsigned char const *state, unsigned int statelen, size_t *dirlen) +{ + size_t newlen, ddirlen ; + size_t sabase = sa->len ; + int wasnull = !sa->s ; + if (!s6rc_sanitize_dir(sa, live, &ddirlen)) return 0 ; + if (!stralloc_cats(sa, ":")) goto err ; + if (!stralloc_cats(sa, suffix)) goto err ; + if (!stralloc_cats(sa, ":XXXXXX")) goto err ; + if (!mkdtemp(sa->s + sabase)) goto err ; + newlen = sa->len-- ; + if (chmod(sa->s + sabase, 0755) < 0) goto delerr ; + if (!stralloc_catb(sa, "/servicedirs", 13)) goto delerr ; /* allocates enough for the next strcpys */ + if (mkdir(sa->s + sabase, 0755) < 0) goto delerr ; + strcpy(sa->s + newlen, "compiled") ; + if (symlink(compiled, sa->s + sabase) < 0) goto delerr ; + strcpy(sa->s + newlen, "scandir") ; + if (symlink(scandir, sa->s + sabase) < 0) goto delerr ; + strcpy(sa->s + newlen, "prefix") ; + if (!openwritenclose_unsafe(sa->s + sabase, prefix, strlen(prefix))) goto delerr ; + strcpy(sa->s + newlen, "state") ; + if (!openwritenclose_unsafe(sa->s + sabase, (char const *)state, statelen)) goto delerr ; + sa->len = newlen ; + sa->s[newlen] = 0 ; + *dirlen = ddirlen ; + return 1 ; + + delerr: + { + int e = errno ; + sa->s[newlen] = 0 ; + rm_rf_in_tmp(sa, sabase) ; + errno = e ; + } + err: + if (wasnull) stralloc_free(sa) ; + else sa->len = sabase ; + return 0 ; +} diff --git a/src/s6-rc/s6-rc-init.c b/src/s6-rc/s6-rc-init.c index c618949..dfc7b7c 100644 --- a/src/s6-rc/s6-rc-init.c +++ b/src/s6-rc/s6-rc-init.c @@ -1,6 +1,5 @@ /* ISC license. */ -#include #include #include #include @@ -11,35 +10,29 @@ #include #include #include -#include +#include #include #include -#define USAGE "s6-rc-init [ -c compiled ] [ -l live ] [ -p prefix ] [ -t timeout ] [ -b ] [ -d ] scandir" +#define USAGE "s6-rc-init [ -c compiled ] [ -l live ] [ -p prefix ] [ -t timeout ] [ -d ] scandir" #define dieusage() strerr_dieusage(100, USAGE) -#define dienomem() strerr_diefu1sys(111, "stralloc_catb") -static size_t llen ; -static stralloc stmp = STRALLOC_ZERO ; - -static void cleanup (void) +static void cleanup (stralloc *sa) { int e = errno ; - stmp.s[llen] = 0 ; - unlink(stmp.s) ; - stmp.s[llen] = ':' ; - rm_rf_in_tmp(&stmp, 0) ; + rm_rf_in_tmp(sa, 0) ; errno = e ; } int main (int argc, char const *const *argv) { - tain_t deadline, tto ; + tain_t deadline ; + stralloc sa = STRALLOC_ZERO ; size_t dirlen ; char const *live = S6RC_LIVE_BASE ; char const *compiled = S6RC_COMPILED_BASE ; char const *prefix = "" ; - int blocking = 0, deref = 0 ; + int deref = 0 ; PROG = "s6-rc-init" ; { unsigned int t = 0 ; @@ -54,156 +47,79 @@ int main (int argc, char const *const *argv) case 'l' : live = l.arg ; break ; case 'p' : prefix = l.arg ; break ; case 't' : if (!uint0_scan(l.arg, &t)) dieusage() ; break ; - case 'b' : blocking = 1 ; break ; + case 'b' : break ; case 'd' : deref = 1 ; break ; default : dieusage() ; } } argc -= l.ind ; argv += l.ind ; - if (t) tain_from_millisecs(&tto, t) ; - else tto = tain_infinite_relative ; + if (t) tain_from_millisecs(&deadline, t) ; + else deadline = tain_infinite_relative ; } if (!argc) dieusage() ; if (!deref && compiled[0] != '/') strerr_dief2x(100, compiled, " is not an absolute path") ; - if (live[0] != '/') - strerr_dief2x(100, live, " is not an absolute path") ; if (argv[0][0] != '/') strerr_dief2x(100, argv[0], " is not an absolute path") ; if (strchr(prefix, '/') || strchr(prefix, '\n')) strerr_dief1x(100, "prefix cannot contain a / or a newline") ; tain_now_g() ; - tain_add_g(&deadline, &tto) ; - - if (!s6rc_sanitize_dir(&stmp, live, &dirlen)) dienomem() ; - llen = stmp.len ; - if (!stralloc_cats(&stmp, ":initial") || !stralloc_0(&stmp)) - strerr_diefu1sys(111, "stralloc_catb") ; + tain_add_g(&deadline, &deadline) ; + if (deref) + { + char *x = realpath(compiled, 0) ; + if (!x) strerr_diefu2sys(111, "realpath ", compiled) ; + compiled = x ; + } { - int fdlock ; - int fdcompiled ; - int ok ; s6rc_db_t db ; - unsigned int n ; - char lfn[llen + 13] ; - char cfn[llen + 23] ; - - - /* Create the real dir, lock it, symlink */ - - unlink(live) ; - rm_rf(stmp.s) ; - if (mkdir(stmp.s, 0755) < 0) strerr_diefu2sys(111, "mkdir ", stmp.s) ; - if (!s6rc_lock(stmp.s, 2, &fdlock, 0, 0, 0, blocking)) - { - cleanup() ; - strerr_diefu2sys(111, "take lock on ", stmp.s) ; - } - memcpy(lfn, stmp.s, llen) ; - lfn[llen] = 0 ; - if (symlink(stmp.s + dirlen, lfn) < 0) - { - cleanup() ; - strerr_diefu4sys(111, "symlink ", stmp.s + dirlen, " to ", lfn) ; - } - - - /* compiled */ - - if (deref) - { - char *x = realpath(compiled, 0) ; - if (!x) strerr_diefu2sys(111, "realpath ", compiled) ; - compiled = x ; - } - fdcompiled = open_readb(compiled) ; + int r ; + int fdcompiled = open_readb(compiled) ; if (fdcompiled < 0) - { - cleanup() ; strerr_diefu2sys(111, "open ", compiled) ; - } - memcpy(lfn + llen, "/compiled", 10) ; - if (symlink(compiled, lfn) < 0) - { - cleanup() ; - strerr_diefu4sys(111, "symlink ", compiled, " to ", lfn) ; - } - - - /* prefix */ - - if (prefix[0]) - { - memcpy(lfn + llen + 1, "prefix", 7) ; - if (!openwritenclose_unsafe(lfn, prefix, strlen(prefix))) - { - cleanup() ; - strerr_diefu2sys(111, "write to ", lfn) ; - } - } - - - /* scandir */ - - memcpy(lfn + llen + 1, "scandir", 8) ; - if (symlink(argv[0], lfn) < 0) + r = s6rc_db_read_sizes(fdcompiled, &db) ; + if (r < 0) + strerr_diefu2sys(111, "read database size in ", compiled) ; + else if (!r) + strerr_dief2x(4, "invalid database size in ", compiled) ; + close(fdcompiled) ; { - cleanup() ; - strerr_diefu4sys(111, "symlink ", argv[0], " to ", lfn) ; + unsigned char state[db.nshort + db.nlong] ; + memset(state, 0, db.nshort + db.nlong) ; + if (!s6rc_livedir_create(&sa, live, PROG, argv[0], prefix, compiled, state, db.nshort + db.nlong, &dirlen)) + strerr_diefu1sys(111, "create live directory") ; } - - - /* state */ - - memcpy(lfn + llen + 1, "state", 6) ; - { - int r = s6rc_db_read_sizes(fdcompiled, &db) ; - if (r <= 0) - { - cleanup() ; - if (r < 0) strerr_diefu2sys(111, "read database size in ", compiled) ; - else strerr_dief2x(4, "invalid database size in ", compiled) ; - } - close(fdcompiled) ; - n = db.nshort + db.nlong ; - { - char zero[n] ; - memset(zero, 0, n) ; - if (!openwritenclose_unsafe(lfn, zero, n)) - { - cleanup() ; - strerr_diefu2sys(111, "write ", lfn) ; - } - } - } - - - /* servicedirs */ - - memcpy(lfn + llen + 1, "servicedirs", 12) ; - memcpy(cfn, lfn, llen + 1) ; - memcpy(cfn + llen + 1, "compiled/servicedirs", 21) ; + } + { + size_t clen = strlen(compiled) ; + char lfn[sa.len + 13] ; + char cfn[clen + 13] ; + memcpy(lfn, sa.s, sa.len) ; + memcpy(lfn + sa.len, "/servicedirs", 13) ; + memcpy(cfn, compiled, clen) ; + memcpy(cfn + clen, "/servicedirs", 13) ; if (!hiercopy(cfn, lfn)) { - cleanup() ; + cleanup(&sa) ; strerr_diefu4sys(111, "recursively copy ", cfn, " to ", lfn) ; } + } + if (!atomic_symlink(sa.s + dirlen, live, PROG)) + { + cleanup(&sa) ; + strerr_diefu4sys(111, "symlink ", sa.s + dirlen, " to ", live) ; + } - - /* start the supervisors */ - - lfn[llen] = 0 ; - ok = s6rc_servicedir_manage_g(lfn, prefix, &deadline) ; - if (!ok) - { - cleanup() ; - strerr_diefu3sys(111, "supervise service directories in ", lfn, "/servicedirs") ; - } - if (ok & 2) - strerr_warnw3x("s6-svscan not running on ", lfn, "/scandir") ; - } + deref = s6rc_servicedir_manage_g(live, prefix, &deadline) ; + if (!deref) + { + cleanup(&sa) ; + strerr_diefu3sys(111, "supervise service directories in ", live, "/servicedirs") ; + } + if (deref & 2) + strerr_warnw2x("s6-svscan not running on ", argv[0]) ; return 0 ; } diff --git a/src/s6-rc/s6-rc-update.c b/src/s6-rc/s6-rc-update.c index 3f77ecb..dc3806b 100644 --- a/src/s6-rc/s6-rc-update.c +++ b/src/s6-rc/s6-rc-update.c @@ -3,6 +3,7 @@ #include /* Solaris doesn't know mkdtemp() is POSIX */ #include #include +#include #include #include #include @@ -32,7 +33,6 @@ #define USAGE "s6-rc-update [ -n ] [ -v verbosity ] [ -t timeout ] [ -l live ] [ -f conversion_file ] [ -b ] newdb" #define dieusage() strerr_dieusage(100, USAGE) #define dienomem() strerr_diefu1sys(111, "build string") ; -#define NEWSUFFIX ":updated:XXXXXX" static char const *live = S6RC_LIVE_BASE ; static size_t livelen = sizeof(S6RC_LIVE_BASE) - 1 ; @@ -324,49 +324,32 @@ static inline void rollback_servicedirs (char const *newlive, unsigned char cons } } -static inline void make_new_livedir (unsigned char const *oldstate, s6rc_db_t const *olddb, unsigned char const *newstate, s6rc_db_t const *newdb, char const *newcompiled, unsigned int *invimage, char const *prefix, size_t prefixlen, stralloc *sa) +static inline void make_new_livedir (unsigned char const *oldstate, s6rc_db_t const *olddb, unsigned char const *newstate, s6rc_db_t const *newdb, char const *newcompiled, unsigned int *invimage, char const *prefix, stralloc *sa) { - size_t tmpbase = satmp.len ; + size_t dirlen, pos, newlen, sdlen ; size_t newclen = strlen(newcompiled) ; - size_t dirlen, llen, newlen, sdlen ; - int e = 0 ; - unsigned int i = 0 ; - if (sareadlink(&satmp, live) < 0) strerr_diefu2sys(111, "readlink ", live) ; - if (!s6rc_sanitize_dir(sa, live, &dirlen)) dienomem() ; - llen = sa->len ; - if (!stralloc_catb(sa, NEWSUFFIX, sizeof(NEWSUFFIX))) dienomem() ; - newlen = --sa->len ; - if (!mkdtemp(sa->s)) strerr_diefu2sys(111, "mkdtemp ", sa->s) ; - if (chmod(sa->s, 0755) < 0) { e = errno ; goto err ; } + unsigned int i = newdb->nlong + newdb->nshort ; + if (sareadlink(sa, live) < 0 || !stralloc_0(sa)) strerr_diefu2sys(111, "readlink ", live) ; + pos = sa->len ; { - size_t tmplen = satmp.len ; - char fn[llen + 9] ; - if (!stralloc_cats(sa, "/scandir") || !stralloc_0(sa)) { e = errno ; goto err ; } - memcpy(fn, sa->s, llen) ; - memcpy(fn + llen, "/scandir", 9) ; - if (sareadlink(&satmp, fn) < 0 || !stralloc_0(&satmp)) { e = errno ; goto err ; } - if (symlink(satmp.s + tmplen, sa->s) < 0) { e = errno ; goto err ; } - satmp.len = tmplen ; - } - sa->len = newlen ; - if (!stralloc_catb(sa, "/prefix", 8)) { e = errno ; goto err ; } - if (!openwritenclose_unsafe(sa->s, prefix, prefixlen)) { e = errno ; goto err ; } - sa->len = newlen ; - if (!stralloc_catb(sa, "/state", 7)) { e = errno ; goto err ; } - { - char tmpstate[newdb->nlong + newdb->nshort] ; - unsigned int i = newdb->nlong + newdb->nshort ; + ssize_t r ; + char sdtarget[PATH_MAX] ; + char sdlink[livelen + 9] ; + unsigned char tmpstate[newdb->nlong + newdb->nshort] ; + memcpy(sdlink, live, livelen) ; + memcpy(sdlink + livelen, "/scandir", 9) ; + r = readlink(sdlink, sdtarget, PATH_MAX) ; + if (r < 0) strerr_diefu2sys(111, "readlink ", sdlink) ; + if (r >= PATH_MAX - 1) strerr_dief3x(100, "target for ", sdlink, " is too long") ; + sdtarget[r] = 0 ; while (i--) tmpstate[i] = newstate[i] & 1 ; - if (!openwritenclose_unsafe(sa->s, tmpstate, newdb->nlong + newdb->nshort)) { e = errno ; goto err ; } + if (!s6rc_livedir_create(sa, live, PROG, sdtarget, prefix, newcompiled, tmpstate, newdb->nlong + newdb->nshort, &dirlen)) + strerr_diefu1sys(111, "create new livedir") ; } - sa->len = newlen ; - if (!stralloc_catb(sa, "/compiled", 10)) { e = errno ; goto err ; } - if (symlink(newcompiled, sa->s) < 0) goto err ; - sa->len = newlen ; - if (!stralloc_catb(sa, "/servicedirs", 13)) { e = errno ; goto err ; } - if (mkdir(sa->s, 0755) < 0) { e = errno ; goto err ; } + newlen = sa->len ; + i = 0 ; + if (!stralloc_catb(sa, "/servicedirs/", 13)) goto rollback ; sdlen = sa->len ; - sa->s[sdlen - 1] = '/' ; for (; i < newdb->nlong ; i++) { @@ -376,8 +359,7 @@ static inline void make_new_livedir (unsigned char const *oldstate, s6rc_db_t co memcpy(newfn + newclen, "/servicedirs/", 13) ; memcpy(newfn + newclen + 13, newdb->string + newdb->services[i].name, newnamelen + 1) ; sa->len = sdlen ; - if (!stralloc_cats(sa, newdb->string + newdb->services[i].name) - || !stralloc_0(sa)) { e = errno ; goto rollback ; } + if (!stralloc_cats(sa, newdb->string + newdb->services[i].name) || !stralloc_0(sa)) goto rollback ; if (newstate[i] & 1) { char const *oldname = newstate[i] & 8 ? olddb->string + olddb->services[invimage[i]].name : newdb->string + newdb->services[i].name ; @@ -386,55 +368,35 @@ static inline void make_new_livedir (unsigned char const *oldstate, s6rc_db_t co memcpy(oldfn, live, livelen) ; memcpy(oldfn + livelen, "/servicedirs/", 13) ; memcpy(oldfn + livelen + 13, oldname, oldnamelen + 1) ; - if (rename(oldfn, sa->s) < 0) goto rollback ; - if (!s6rc_servicedir_copy_online(newfn, sa->s)) { i++ ; e = errno ; goto rollback ; } + if (rename(oldfn, sa->s + pos) < 0) goto rollback ; + if (!s6rc_servicedir_copy_online(newfn, sa->s + pos)) { i++ ; goto rollback ; } } - else if (!s6rc_servicedir_copy_offline(newfn, sa->s)) { e = errno ; goto rollback ; } + else if (!s6rc_servicedir_copy_offline(newfn, sa->s + pos)) goto rollback ; } - sa->len = newlen ; - sa->s[sa->len++] = 0 ; - { - char tmpfn[llen + 5] ; - memcpy(tmpfn, sa->s, llen) ; - memcpy(tmpfn + llen, ".new", 5) ; - if (unlink(tmpfn) < 0 && errno != ENOENT) { e = errno ; goto rollback ; } - if (symlink(sa->s + dirlen, tmpfn) < 0) { e = errno ; goto rollback ; } + sa->s[sa->len] = 0 ; /* The point of no return is here */ - if (rename(tmpfn, live) < 0) - { - e = errno ; - unlink(tmpfn) ; - goto rollback ; - } - } - - if (verbosity >= 2) - strerr_warni1x("successfully switched to new database") ; + if (!atomic_symlink(sa->s + dirlen, live, "s6-rc-update_atomic_symlink")) goto rollback ; + if (verbosity >= 2) strerr_warni1x("successfully switched to new database") ; /* scandir cleanup, then old livedir cleanup */ - sa->len = dirlen ; - if (!stralloc_catb(sa, satmp.s + tmpbase, satmp.len - tmpbase) || !stralloc_0(sa)) - dienomem() ; i = olddb->nlong ; while (i--) s6rc_servicedir_unsupervise(sa->s, prefix, olddb->string + olddb->services[i].name, (oldstate[i] & 33) == 1) ; - rm_rf(sa->s) ; - + rm_rf_in_tmp(sa, 0) ; sa->len = 0 ; - satmp.len = tmpbase ; return ; rollback: - sa->len = newlen ; - sa->s[sa->len++] = 0 ; - rollback_servicedirs(sa->s, newstate, invimage, olddb, newdb, i) ; - err: - sa->len = newlen ; - sa->s[sa->len++] = 0 ; - rm_rf(sa->s) ; - errno = e ; + { + int e = errno ; + sa->len = newlen ; + sa->s[sa->len++] = 0 ; + rollback_servicedirs(sa->s + pos, newstate, invimage, olddb, newdb, i) ; + rm_rf_in_tmp(sa, 0) ; + errno = e ; + } strerr_diefu2sys(111, "make new live directory in ", sa->s) ; } @@ -642,8 +604,6 @@ int main (int argc, char const *const *argv, char const *const *envp) if (!argc) dieusage() ; if (argv[0][0] != '/') strerr_dief2x(100, argv[0], " is not an absolute path") ; - if (live[0] != '/') - strerr_dief2x(100, live, " is not an absolute path") ; livelen = strlen(live) ; { @@ -809,12 +769,12 @@ int main (int argc, char const *const *argv, char const *const *envp) if (verbosity >= 2) strerr_warni1x("updating state and service directories") ; - make_new_livedir(oldstate, &olddb, newstate, &newdb, argv[0], invimage, prefix, prefixlen, &sa) ; + make_new_livedir(oldstate, &olddb, newstate, &newdb, argv[0], invimage, prefix, &sa) ; + stralloc_free(&sa) ; r = s6rc_servicedir_manage_g(live, prefix, &deadline) ; if (!r) strerr_diefu2sys(111, "manage new service directories in ", live) ; if (r & 2) strerr_warnw3x("s6-svscan not running on ", live, "/scandir") ; - /* Adjust stored pipes */ if (verbosity >= 2) -- cgit v1.2.3