diff options
Diffstat (limited to 'src/libs6rc/s6rc_db_init.c')
| -rw-r--r-- | src/libs6rc/s6rc_db_init.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/src/libs6rc/s6rc_db_init.c b/src/libs6rc/s6rc_db_init.c new file mode 100644 index 0000000..075d0c3 --- /dev/null +++ b/src/libs6rc/s6rc_db_init.c @@ -0,0 +1,140 @@ +/* ISC license. */ + +#include <stdint.h> +#include <string.h> +#include <errno.h> +#include <sys/stat.h> +#include <sys/mman.h> + +#include <skalibs/uint32.h> +#include <skalibs/alloc.h> +#include <skalibs/buffer.h> +#include <skalibs/djbunix.h> +#include <skalibs/cdb.h> +#include <skalibs/sha256.h> + +#include <s6-rc/db.h> + +#include <skalibs/posixishard.h> + +static int gethu32 (buffer *b, SHA256Schedule *ctx, uint32_t *n) +{ + if (buffer_get(b, (char *)n, 4) < 4) return 0 ; + sha256_update(ctx, (char *)n, 4) ; + return 1 ; +} + +int s6rc_db_init (s6rc_db_t *db, char const *dir) +{ + SHA256Schedule ctx = SHA256_INIT() ; + uint32_t ntotal, ndeps, nproducers, storagelen, nargv ; + size_t len = strlen(dir) ; + buffer b ; + int fd ; + char buf[4096] ; + char fn[len + 13] ; + memcpy(fn, dir, len) ; + memcpy(fn + len, "/db_nomap", 10) ; + fd = openc_read(fn) ; + if (fd == -1) return 0 ; + buffer_init(&b, &buffer_read, fd, buf, 4096) ; + { + uint32_t canary ; + if (!gethu32(&b, &canary)) goto err0 ; + if (canary != 0x11223344u) { errno = EILSEQ ; goto err0 ; } + } + if (!gethu32(&b, &ctx, &ntotal)) goto err0 ; + if (!gethu32(&b, &ctx, &ndeps)) goto err0 ; + if (!gethu32(&b, &ctx, &nproducers)) goto err0 ; + if (!gethu32(&b, &ctx, &storagelen)) goto err0 ; + if (!gethu32(&b, &ctx, &nargv)) goto err0 ; + if (nargv > S6RC_ARGV_MAX) goto eproto0 ; + + { + uint32_t argvs[nargv ? nargv : 1] ; + if (buffer_get(&b, (char *)argvs, nargv * 4) < nargv * 4) goto err0 ; + { + char c ; + ssize_t r = buffer_get(&b, &c, 1) ; + if (r < 0) goto err0 ; + if (r) goto eproto0 ; + } + fd_close(fd) ; + sha256_update(&ctx, (char *)argvs, nargv * 4) ; + memcpy(fn + len, "/db", 4) ; + + { + struct stat st ; + void *map ; + fd = openc_read(fn) ; + if (fd == -1) return 0 ; + if (fstat(fd, &st) == -1) goto err0 ; + if (!S_ISREG(st.st_mode)) goto eproto0 ; + if (st.st_size < 8 * S6RC_STYPE_N) goto eproto0 ; + map = mmap(0, st.st_size, PROT_READ, MAP_SHARED, fd, 0) ; + if (map == MAP_FAILED) goto err0 ; + fd_close(fd) ; + db->size = st.st_size ; + db->map = map ; + } + db->n = (uint32_t const *)db->map ; + if (ntotal != db->n[0] + db->n[1] + db->n[2] + db->n[3] + db->n[4] + db->n[5] + db->n[6] + db->n[7] + db->n[8] + db->n[9]) + { + errno = EPROTO ; + goto err1 ; + } + + memcpy(fn + len, "/resolve.cdb", 13) ; + if (!cdb_init(&db->resolve, fn)) goto err1 ; + + { + ssize_t r ; + memcpy(fn + len, "/hash", 6) ; + r = openreadnclose(fn, buf+32, 33) ; + if (r == 33) goto eproto2 ; + if (r < 32) goto err2 ; + sha256_update(&ctx, db->map, db->size) ; + sha256_update(&ctx, c->map, c->size) ; + sha256_final(&ctx, buf) ; + if (memcmp(buf, buf+32, 32)) goto eproto2 ; + } + + db->longruns = (s6rc_longrun_t const *)(db->map + 4 * 2 * S6RC_STYPE_N) ; + db->oneshots = (s6rc_oneshot_t const *)(db->longruns + db->n[S6RC_STYPE_LONGRUN] + db->n[S6RC_STYPE_N + S6RC_STYPE_LONGRUN]) ; + db->externals = (s6rc_external_t const *)(db->oneshots + db->n[S6RC_STYPE_ONESHOT] + db->n[S6RC_STYPE_N + S6RC_STYPE_ONESHOT]) ; + db->bundles = (s6rc_bundle_t const *)(db->externals + db->n[S6RC_STYPE_EXTERNAL] + db->n[S6RC_STYPE_N + S6RC_STYPE_EXTERNAL]) ; + db->virtuals = (s6rc_bundle_t const *)(db->bundles + db->n[S6RC_STYPE_BUNDLE] + db->n[S6RC_STYPE_N + S6RC_STYPE_BUNDLE]) ; + db->deps[0] = (uint32_t const *)(db->virtuals + db->n[S6RC_STYPE_VIRTUAL] + db->n[S6RC_STYPE_N + S6RC_STYPE_VIRTUAL]) ; + db->deps[1] = db->deps[0] + ndeps ; + db->producers = db->deps[1] + ndeps ; + db->deptypes[0] = (uint8_t const *)(db->producers + nproducers) ; + db->deptypes[1] = db->deptypes[0] + ndeps ; + db->storage = (char const *)(db->deptypes[1] + ndeps) ; + if (db->storage + storagelen != db->map + db->size) goto eproto2 ; + + db->argvs = (char const **)alloc(sizeof(char const *) * nargv) ; + if (!db->argvs) goto err2 ; + for (uint32_t i = 0 ; i < nargv ; i++) + db->argvs[i] = argvs[i] ? db->storage + argvs[i] : 0 ; + } + return 1 ; + + eproto2: + errno = EPROTO ; + err2: + cdb_free(&db->resolve) ; + err1: + { + int e = errno ; + munmap(db->map, db->size) ; + errno = e ; + } + db->map = 0 ; + return 0 ; + + eproto0: + errno = EPROTO ; + err0: + fd_close(fd) ; + return 0 ; +} |