tdb2: rework io functions to return enum TDB_ERROR.
[ccan] / ccan / tdb2 / io.c
index f326d98ba6d03e4c49e37409ae61280ae8a894bb..a0c5f5232554a3d37f1b36f3d1e2ff0fdda8657e 100644 (file)
@@ -67,7 +67,8 @@ void tdb_mmap(struct tdb_context *tdb)
    if necessary
    note that "len" is the minimum length needed for the db
 */
-static int tdb_oob(struct tdb_context *tdb, tdb_off_t len, bool probe)
+static enum TDB_ERROR tdb_oob(struct tdb_context *tdb, tdb_off_t len,
+                             bool probe)
 {
        struct stat st;
        enum TDB_ERROR ecode;
@@ -87,20 +88,19 @@ static int tdb_oob(struct tdb_context *tdb, tdb_off_t len, bool probe)
                                 (long long)len,
                                 (long long)tdb->map_size);
                }
-               return -1;
+               return TDB_ERR_IO;
        }
 
        ecode = tdb_lock_expand(tdb, F_RDLCK);
        if (ecode != TDB_SUCCESS) {
-               tdb->ecode = ecode;
-               return -1;
+               return ecode;
        }
 
        if (fstat(tdb->fd, &st) != 0) {
                tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
                           "Failed to fstat file: %s", strerror(errno));
                tdb_unlock_expand(tdb, F_RDLCK);
-               return -1;
+               return TDB_ERR_IO;
        }
 
        tdb_unlock_expand(tdb, F_RDLCK);
@@ -111,7 +111,7 @@ static int tdb_oob(struct tdb_context *tdb, tdb_off_t len, bool probe)
                                   "tdb_oob len %zu beyond eof at %zu",
                                   (size_t)len, st.st_size);
                }
-               return -1;
+               return TDB_ERR_IO;
        }
 
        /* Unmap, update size, remap */
@@ -119,7 +119,7 @@ static int tdb_oob(struct tdb_context *tdb, tdb_off_t len, bool probe)
 
        tdb->map_size = st.st_size;
        tdb_mmap(tdb);
-       return 0;
+       return TDB_SUCCESS;
 }
 
 /* Endian conversion: we only ever deal with 8 byte quantities */
@@ -178,6 +178,7 @@ int zero_out(struct tdb_context *tdb, tdb_off_t off, tdb_len_t len)
 {
        char buf[8192] = { 0 };
        void *p = tdb->methods->direct(tdb, off, len, true);
+       enum TDB_ERROR ecode;
 
        assert(!tdb->read_only);
        if (p) {
@@ -186,8 +187,11 @@ int zero_out(struct tdb_context *tdb, tdb_off_t off, tdb_len_t len)
        }
        while (len) {
                unsigned todo = len < sizeof(buf) ? len : sizeof(buf);
-               if (tdb->methods->twrite(tdb, off, buf, todo) == -1)
+               ecode = tdb->methods->twrite(tdb, off, buf, todo);
+               if (ecode != TDB_SUCCESS) {
+                       tdb->ecode = ecode;
                        return -1;
+               }
                len -= todo;
                off += todo;
        }
@@ -211,22 +215,25 @@ tdb_off_t tdb_read_off(struct tdb_context *tdb, tdb_off_t off)
 }
 
 /* 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)
+static enum TDB_ERROR tdb_write(struct tdb_context *tdb, tdb_off_t off,
+                               const void *buf, tdb_len_t len)
 {
+       enum TDB_ERROR ecode;
+
        if (tdb->read_only) {
-               tdb_logerr(tdb, TDB_ERR_RDONLY, TDB_LOG_USE_ERROR,
-                          "Write to read-only database");
-               return -1;
+               return tdb_logerr(tdb, TDB_ERR_RDONLY, TDB_LOG_USE_ERROR,
+                                 "Write to read-only database");
        }
 
        /* FIXME: Bogus optimization? */
        if (len == 0) {
-               return 0;
+               return TDB_SUCCESS;
        }
 
-       if (tdb->methods->oob(tdb, off + len, 0) != 0)
-               return -1;
+       ecode = tdb->methods->oob(tdb, off + len, 0);
+       if (ecode != TDB_SUCCESS) {
+               return ecode;
+       }
 
        if (tdb->map_ptr) {
                memcpy(off + (char *)tdb->map_ptr, buf, len);
@@ -238,22 +245,24 @@ static int tdb_write(struct tdb_context *tdb, tdb_off_t off,
                        if (ret >= 0)
                                errno = ENOSPC;
 
-                       tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                  "tdb_write: %zi at %zu len=%zu (%s)",
-                                  ret, (size_t)off, (size_t)len,
-                                  strerror(errno));
-                       return -1;
+                       return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+                                         "tdb_write: %zi at %zu len=%zu (%s)",
+                                         ret, (size_t)off, (size_t)len,
+                                         strerror(errno));
                }
        }
-       return 0;
+       return TDB_SUCCESS;
 }
 
 /* read a lump of data at a specified offset */
-static int tdb_read(struct tdb_context *tdb, tdb_off_t off, void *buf,
-                   tdb_len_t len)
+static enum TDB_ERROR tdb_read(struct tdb_context *tdb, tdb_off_t off,
+                              void *buf, tdb_len_t len)
 {
-       if (tdb->methods->oob(tdb, off + len, 0) != 0) {
-               return -1;
+       enum TDB_ERROR ecode;
+
+       ecode = tdb->methods->oob(tdb, off + len, 0);
+       if (ecode != TDB_SUCCESS) {
+               return ecode;
        }
 
        if (tdb->map_ptr) {
@@ -261,22 +270,22 @@ static int tdb_read(struct tdb_context *tdb, tdb_off_t off, void *buf,
        } else {
                ssize_t r = pread(tdb->fd, buf, len, off);
                if (r != len) {
-                       tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
-                                  "tdb_read failed with %zi at %zu "
-                                  "len=%zu (%s) map_size=%zu",
-                                  r, (size_t)off, (size_t)len,
-                                  strerror(errno),
-                                  (size_t)tdb->map_size);
-                       return -1;
+                       return tdb_logerr(tdb, TDB_ERR_IO, TDB_LOG_ERROR,
+                                         "tdb_read failed with %zi at %zu "
+                                         "len=%zu (%s) map_size=%zu",
+                                         r, (size_t)off, (size_t)len,
+                                         strerror(errno),
+                                         (size_t)tdb->map_size);
                }
        }
-       return 0;
+       return TDB_SUCCESS;
 }
 
 int tdb_write_convert(struct tdb_context *tdb, tdb_off_t off,
                      const void *rec, size_t len)
 {
-       int ret;
+       enum TDB_ERROR ecode;
+
        if (unlikely((tdb->flags & TDB_CONVERT))) {
                void *conv = malloc(len);
                if (!conv) {
@@ -286,21 +295,30 @@ int tdb_write_convert(struct tdb_context *tdb, tdb_off_t off,
                        return -1;
                }
                memcpy(conv, rec, len);
-               ret = tdb->methods->twrite(tdb, off,
+               ecode = tdb->methods->twrite(tdb, off,
                                           tdb_convert(tdb, conv, len), len);
                free(conv);
-       } else
-               ret = tdb->methods->twrite(tdb, off, rec, len);
+       } else {
+               ecode = tdb->methods->twrite(tdb, off, rec, len);
+       }
 
-       return ret;
+       if (ecode != TDB_SUCCESS) {
+               tdb->ecode = ecode;
+               return -1;
+       }
+       return 0;
 }
 
 int tdb_read_convert(struct tdb_context *tdb, tdb_off_t off,
                      void *rec, size_t len)
 {
-       int ret = tdb->methods->tread(tdb, off, rec, len);
+       enum TDB_ERROR ecode = tdb->methods->tread(tdb, off, rec, len);
        tdb_convert(tdb, rec, len);
-       return ret;
+       if (ecode != TDB_SUCCESS) {
+               tdb->ecode = ecode;
+               return -1;
+       }
+       return 0;
 }
 
 int tdb_write_off(struct tdb_context *tdb, tdb_off_t off, tdb_off_t val)
@@ -326,6 +344,7 @@ static void *_tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset,
                             tdb_len_t len, unsigned int prefix)
 {
        void *buf;
+       enum TDB_ERROR ecode;
 
        /* some systems don't like zero length malloc */
        buf = malloc(prefix + len ? prefix + len : 1);
@@ -333,10 +352,13 @@ static void *_tdb_alloc_read(struct tdb_context *tdb, tdb_off_t offset,
                tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_USE_ERROR,
                           "tdb_alloc_read malloc failed len=%zu",
                           (size_t)(prefix + len));
-       } else if (unlikely(tdb->methods->tread(tdb, offset, buf+prefix, len)
-                           == -1)) {
-               free(buf);
-               buf = NULL;
+       } else {
+               ecode = tdb->methods->tread(tdb, offset, buf+prefix, len);
+               if (unlikely(ecode != TDB_SUCCESS)) {
+                       tdb->ecode = ecode;
+                       free(buf);
+                       buf = NULL;
+               }
        }
        return buf;
 }
@@ -372,22 +394,21 @@ static int fill(struct tdb_context *tdb,
 
 /* expand a file.  we prefer to use ftruncate, as that is what posix
   says to use for mmap expansion */
-static int tdb_expand_file(struct tdb_context *tdb, tdb_len_t addition)
+static enum TDB_ERROR tdb_expand_file(struct tdb_context *tdb,
+                                     tdb_len_t addition)
 {
        char buf[8192];
 
        if (tdb->read_only) {
-               tdb_logerr(tdb, TDB_ERR_RDONLY, TDB_LOG_USE_ERROR,
-                          "Expand on read-only database");
-               return -1;
+               return tdb_logerr(tdb, TDB_ERR_RDONLY, TDB_LOG_USE_ERROR,
+                                 "Expand on read-only database");
        }
 
        if (tdb->flags & TDB_INTERNAL) {
                char *new = realloc(tdb->map_ptr, tdb->map_size + addition);
                if (!new) {
-                       tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
-                                  "No memory to expand database");
-                       return -1;
+                       return tdb_logerr(tdb, TDB_ERR_OOM, TDB_LOG_ERROR,
+                                         "No memory to expand database");
                }
                tdb->map_ptr = new;
                tdb->map_size += addition;
@@ -405,11 +426,11 @@ static int tdb_expand_file(struct tdb_context *tdb, tdb_len_t addition)
                   disk. This must be done with write, not via mmap */
                memset(buf, 0x43, sizeof(buf));
                if (fill(tdb, buf, sizeof(buf), tdb->map_size, addition) == -1)
-                       return -1;
+                       return tdb->ecode;
                tdb->map_size += addition;
                tdb_mmap(tdb);
        }
-       return 0;
+       return TDB_SUCCESS;
 }
 
 const void *tdb_access_read(struct tdb_context *tdb,
@@ -517,7 +538,7 @@ static void *tdb_direct(struct tdb_context *tdb, tdb_off_t off, size_t len,
        if (unlikely(!tdb->map_ptr))
                return NULL;
 
-       if (unlikely(tdb_oob(tdb, off + len, true) == -1))
+       if (unlikely(tdb_oob(tdb, off + len, true) != TDB_SUCCESS))
                return NULL;
        return (char *)tdb->map_ptr + off;
 }