lib-index: mail_cache_map_all() - Separate error and corruption handling

diff --git a/src/lib-index/mail-cache-compress.c b/src/lib-index/mail-cache-compress.c
index 1d0c17781788bd65ef5f90ae86be8b1691aa19c3..088c71a5b6dd8ebb6f6b390fdac3e9652bd57e10 100644 (file)
--- a/src/lib-index/mail-cache-compress.c
+++ b/src/lib-index/mail-cache-compress.c
@@ -443,7 +443,7 @@ static int mail_cache_compress_locked(struct mail_cache *cache,
        }
        if (cache->fd != -1) {
                /* make sure we have mapped it before reading. */
-               if (mail_cache_map_all(cache) < 0)
+               if (mail_cache_map_all(cache) <= 0)
                        return -1;
        }
 
@@ -459,7 +459,7 @@ static int mail_cache_compress_locked(struct mail_cache *cache,
        if (cache->file_cache != NULL)
                file_cache_set_fd(cache->file_cache, cache->fd);
 
-       if (mail_cache_map_all(cache) < 0)
+       if (mail_cache_map_all(cache) <= 0)
                return -1;
        if (mail_cache_header_fields_read(cache) < 0)
                return -1;

diff --git a/src/lib-index/mail-cache-private.h b/src/lib-index/mail-cache-private.h
index 51be272d7d910a6fa9f30e31576a92e5b9326958..c9c89856448e94fd666c991835e2ed37f7c1c16d 100644 (file)
--- a/src/lib-index/mail-cache-private.h
+++ b/src/lib-index/mail-cache-private.h
@@ -250,10 +250,12 @@ mail_cache_transaction_lookup_rec(struct mail_cache_transaction_ctx *ctx,
                                  unsigned int *trans_next_idx);
 
 /* Return data from the specified position in the cache file. Returns 1 if
-   successful, 0 if offset/size points outside the cache file, -1 if error. */
+   successful, 0 if offset/size points outside the cache file, -1 if I/O
+   error. */
 int mail_cache_map(struct mail_cache *cache, size_t offset, size_t size,
                   const void **data_r);
-/* Map the whole cache file into memory. Returns 0 if ok, -1 if error. */
+/* Map the whole cache file into memory. Returns 1 if ok, 0 if corrupted
+   (and deleted), -1 if I/O error. */
 int mail_cache_map_all(struct mail_cache *cache);
 void mail_cache_file_close(struct mail_cache *cache);
 int mail_cache_reopen(struct mail_cache *cache);

diff --git a/src/lib-index/mail-cache.c b/src/lib-index/mail-cache.c
index 763e8ba558f6f720cab0b7b99739fcad3ff3912c..545ba5f5fcdf23e34881aa7345a28965947583cd 100644 (file)
--- a/src/lib-index/mail-cache.c
+++ b/src/lib-index/mail-cache.c
@@ -146,7 +146,7 @@ static int mail_cache_try_open(struct mail_cache *cache)
 
        mail_cache_init_file_cache(cache);
 
-       if (mail_cache_map_all(cache) < 0) {
+       if (mail_cache_map_all(cache) <= 0) {
                mail_cache_file_close(cache);
                return -1;
        }
@@ -334,10 +334,12 @@ static bool mail_cache_verify_header(struct mail_cache *cache,
 
 static int
 mail_cache_map_finish(struct mail_cache *cache, uoff_t offset, size_t size,
-                     const void *hdr_data, bool copy_hdr)
+                     const void *hdr_data, bool copy_hdr, bool *corrupted_r)
 {
        const struct mail_cache_header *hdr = hdr_data;
 
+       *corrupted_r = FALSE;
+
        if (offset == 0) {
                /* verify the header validity only with offset=0. this way
                   we won't waste time re-verifying it all the time */
@@ -347,6 +349,7 @@ mail_cache_map_finish(struct mail_cache *cache, uoff_t offset, size_t size,
                                cache->hdr->file_seq != 0 ?
                                cache->hdr->file_seq : 0;
                        cache->hdr = NULL;
+                       *corrupted_r = TRUE;
                        return -1;
                }
        }
@@ -371,7 +374,7 @@ mail_cache_map_finish(struct mail_cache *cache, uoff_t offset, size_t size,
 
 static int
 mail_cache_map_with_read(struct mail_cache *cache, size_t offset, size_t size,
-                        const void **data_r)
+                        const void **data_r, bool *corrupted_r)
 {
        const void *hdr_data;
        void *data;
@@ -386,7 +389,8 @@ mail_cache_map_with_read(struct mail_cache *cache, size_t offset, size_t size,
                *data_r = CONST_PTR_OFFSET(cache->read_buf->data,
                                           offset - cache->read_offset);
                hdr_data = offset == 0 ? *data_r : NULL;
-               return mail_cache_map_finish(cache, offset, size, hdr_data, TRUE);
+               return mail_cache_map_finish(cache, offset, size, hdr_data,
+                                            TRUE, corrupted_r);
        } else {
                buffer_set_used_size(cache->read_buf, 0);
        }
@@ -416,16 +420,20 @@ mail_cache_map_with_read(struct mail_cache *cache, size_t offset, size_t size,
        *data_r = data;
        hdr_data = offset == 0 ? *data_r : NULL;
        return mail_cache_map_finish(cache, offset,
-                                    cache->read_buf->used, hdr_data, TRUE);
+                                    cache->read_buf->used, hdr_data,
+                                    TRUE, corrupted_r);
 }
 
-int mail_cache_map(struct mail_cache *cache, size_t offset, size_t size,
-                  const void **data_r)
+static int
+mail_cache_map_full(struct mail_cache *cache, size_t offset, size_t size,
+                   const void **data_r, bool *corrupted_r)
 {
        struct stat st;
        const void *data;
        ssize_t ret;
 
+       *corrupted_r = FALSE;
+
        if (size == 0)
                size = sizeof(struct mail_cache_header);
 
@@ -450,7 +458,8 @@ int mail_cache_map(struct mail_cache *cache, size_t offset, size_t size,
 
        cache->remap_counter++;
        if (cache->map_with_read)
-               return mail_cache_map_with_read(cache, offset, size, data_r);
+               return mail_cache_map_with_read(cache, offset, size, data_r,
+                                               corrupted_r);
 
        if (cache->file_cache != NULL) {
                ret = file_cache_read(cache->file_cache, offset, size);
@@ -473,7 +482,8 @@ int mail_cache_map(struct mail_cache *cache, size_t offset, size_t size,
                *data_r = offset > cache->mmap_length ? NULL :
                        CONST_PTR_OFFSET(data, offset);
                return mail_cache_map_finish(cache, offset, size,
-                                            offset == 0 ? data : NULL, TRUE);
+                                            offset == 0 ? data : NULL, TRUE,
+                                            corrupted_r);
        }
 
        if (offset < cache->mmap_length &&
@@ -517,16 +527,32 @@ int mail_cache_map(struct mail_cache *cache, size_t offset, size_t size,
        *data_r = offset > cache->mmap_length ? NULL :
                CONST_PTR_OFFSET(cache->mmap_base, offset);
        return mail_cache_map_finish(cache, offset, size,
-                                    cache->mmap_base, FALSE);
+                                    cache->mmap_base, FALSE, corrupted_r);
+}
+
+int mail_cache_map(struct mail_cache *cache, size_t offset, size_t size,
+                  const void **data_r)
+{
+       i_assert(offset != 0);
+
+       bool corrupted;
+       int ret = mail_cache_map_full(cache, offset, size, data_r, &corrupted);
+       i_assert(!corrupted);
+       return ret;
 }
 
 int mail_cache_map_all(struct mail_cache *cache)
 {
        const void *data;
+       bool corrupted;
 
-       int ret = mail_cache_map(cache, 0, 0, &data);
+       int ret = mail_cache_map_full(cache, 0, 0, &data, &corrupted);
        i_assert(ret != 0);
-       return ret < 0 ? -1 : 0;
+       if (corrupted) {
+               i_assert(ret == -1);
+               return 0;
+       }
+       return ret < 0 ? -1 : 1;
 }
 
 int mail_cache_open_and_verify(struct mail_cache *cache)
@@ -740,9 +766,9 @@ mail_cache_lock_full(struct mail_cache *cache, bool nonblock)
        }
        if (cache->read_buf != NULL)
                buffer_set_used_size(cache->read_buf, 0);
-       if (mail_cache_map_all(cache) < 0) {
+       if ((ret = mail_cache_map_all(cache)) <= 0) {
                (void)mail_cache_unlock(cache);
-               return -1;
+               return ret;
        }
        cache->hdr_copy = *cache->hdr;
        return 1;