tdb2: now checking a new empty database works.

[ccan] / ccan / tdb2 / io.c

diff --git a/ccan/tdb2/io.c b/ccan/tdb2/io.c
index 5910fc543d6dd64b3df56d2ba8376752bf25b6b8..9572e7412eccc4d6f3666c6ab11d786f7c08e91e 100644 (file)
--- a/ccan/tdb2/io.c
+++ b/ccan/tdb2/io.c
@@ -125,11 +125,8 @@ static void *tdb_direct(struct tdb_context *tdb, tdb_off_t off, size_t len)
 /* Either make a copy into pad and return that, or return ptr into mmap. */
 /* Note: pad has to be a real object, so we can't get here if len
  * overflows size_t */
-/* FIXME: Transaction */
 void *tdb_get(struct tdb_context *tdb, tdb_off_t off, void *pad, size_t len)
 {
-       ssize_t r;
-
        if (likely(!(tdb->flags & TDB_CONVERT))) {
                void *ret = tdb_direct(tdb, off, len);
                if (ret)
@@ -139,18 +136,8 @@ void *tdb_get(struct tdb_context *tdb, tdb_off_t off, void *pad, size_t len)
        if (unlikely(tdb_oob(tdb, off + len, false) == -1))
                return NULL;
 
-       r = pread(tdb->fd, pad, len, off);
-       if (r != (ssize_t)len) {
-               /* Ensure ecode is set for log fn. */
-               tdb->ecode = TDB_ERR_IO;
-               tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv,
-                        "tdb_read failed at %llu "
-                        "len=%lld ret=%lld (%s) map_size=%lld\n",
-                        (long long)off, (long long)len,
-                        (long long)r, strerror(errno),
-                        (long long)tdb->map_size);
+       if (tdb->methods->read(tdb, off, pad, len) == -1)
                return NULL;
-       }
        return tdb_convert(tdb, pad, len);
 }
 
@@ -249,7 +236,7 @@ tdb_off_t tdb_read_off(struct tdb_context *tdb, tdb_off_t off)
 {
        tdb_off_t pad, *ret;
 
-       ret = tdb_get(tdb, off, &pad, sizeof(ret));
+       ret = tdb_get(tdb, off, &pad, sizeof(pad));
        if (!ret) {
                return TDB_OFF_ERR;
        }
@@ -260,7 +247,7 @@ tdb_off_t tdb_read_off(struct tdb_context *tdb, tdb_off_t off)
 bool tdb_pwrite_all(int fd, const void *buf, size_t len, tdb_off_t off)
 {
        while (len) {
-               size_t ret;
+               ssize_t ret;
                ret = pwrite(fd, buf, len, off);
                if (ret < 0)
                        return false;
@@ -268,13 +255,51 @@ bool tdb_pwrite_all(int fd, const void *buf, size_t len, tdb_off_t off)
                        errno = ENOSPC;
                        return false;
                }
-               buf += ret;
+               buf = (char *)buf + ret;
                off += ret;
                len -= ret;
        }
        return true;
 }
 
+/* Even on files, we can get partial reads due to signals. */
+bool tdb_pread_all(int fd, void *buf, size_t len, tdb_off_t off)
+{
+       while (len) {
+               ssize_t ret;
+               ret = pread(fd, buf, len, off);
+               if (ret < 0)
+                       return false;
+               if (ret == 0) {
+                       /* ETOOSHORT? */
+                       errno = EWOULDBLOCK;
+                       return false;
+               }
+               buf = (char *)buf + ret;
+               off += ret;
+               len -= ret;
+       }
+       return true;
+}
+
+bool tdb_read_all(int fd, void *buf, size_t len)
+{
+       while (len) {
+               ssize_t ret;
+               ret = read(fd, buf, len);
+               if (ret < 0)
+                       return false;
+               if (ret == 0) {
+                       /* ETOOSHORT? */
+                       errno = EWOULDBLOCK;
+                       return false;
+               }
+               buf = (char *)buf + ret;
+               len -= ret;
+       }
+       return true;
+}
+
 /* write a lump of data at a specified offset */
 static int tdb_write(struct tdb_context *tdb, tdb_off_t off, 
                     const void *buf, tdb_len_t len)
@@ -316,15 +341,14 @@ static int tdb_read(struct tdb_context *tdb, tdb_off_t off, void *buf,
        if (tdb->map_ptr) {
                memcpy(buf, off + (char *)tdb->map_ptr, len);
        } else {
-               ssize_t ret = pread(tdb->fd, buf, len, off);
-               if (ret != (ssize_t)len) {
+               if (!tdb_pread_all(tdb->fd, buf, len, off)) {
                        /* Ensure ecode is set for log fn. */
                        tdb->ecode = TDB_ERR_IO;
                        tdb->log(tdb, TDB_DEBUG_FATAL, tdb->log_priv,
                                 "tdb_read failed at %lld "
-                                "len=%lld ret=%lld (%s) map_size=%lld\n",
+                                "len=%lld (%s) map_size=%lld\n",
                                 (long long)off, (long long)len,
-                                (long long)ret, strerror(errno),
+                                strerror(errno),
                                 (long long)tdb->map_size);
                        return -1;
                }
@@ -376,17 +400,17 @@ uint64_t hash_record(struct tdb_context *tdb, tdb_off_t off)
        void *key;
        uint64_t klen, hash;
 
-       r = tdb_get(tdb, off, &pad, sizeof(*r));
+       r = tdb_get(tdb, off, &pad, sizeof(pad));
        if (!r)
                /* FIXME */
                return 0;
 
        klen = rec_key_length(r);
-       key = tdb_direct(tdb, off + sizeof(*r), klen);
+       key = tdb_direct(tdb, off + sizeof(pad), klen);
        if (likely(key))
                return tdb_hash(tdb, key, klen);
 
-       key = tdb_alloc_read(tdb, off + sizeof(*r), klen);
+       key = tdb_alloc_read(tdb, off + sizeof(pad), klen);
        if (unlikely(!key))
                return 0;
        hash = tdb_hash(tdb, key, klen);