On wrong plocate.db header or version, output the filename in the error message.

Suggested by Trent W. Buck (Debian bug #996735).

diff --git a/plocate.cpp b/plocate.cpp
index 1c0b3d0463f09ea04a5f9a39156d91a1e089c7fe..6b8b3d8dcad564ba335ba957864363cec8ddf4ab 100644 (file)
--- a/plocate.cpp
+++ b/plocate.cpp
@@ -66,7 +66,7 @@ ZSTD_DDict *ddict = nullptr;
 
 class Corpus {
 public:
-       Corpus(int fd, IOUringEngine *engine);
+       Corpus(int fd, const char *filename_for_errors, IOUringEngine *engine);
        ~Corpus();
        void find_trigram(uint32_t trgm, function<void(const Trigram *trgmptr, size_t len)> cb);
        void get_compressed_filename_block(uint32_t docid, function<void(string_view)> cb) const;
@@ -84,7 +84,7 @@ public:
        Header hdr;
 };
 
-Corpus::Corpus(int fd, IOUringEngine *engine)
+Corpus::Corpus(int fd, const char *filename_for_errors, IOUringEngine *engine)
        : fd(fd), engine(engine)
 {
        if (flush_cache) {
@@ -98,11 +98,11 @@ Corpus::Corpus(int fd, IOUringEngine *engine)
 
        complete_pread(fd, &hdr, sizeof(hdr), /*offset=*/0);
        if (memcmp(hdr.magic, "\0plocate", 8) != 0) {
-               fprintf(stderr, "plocate.db is corrupt or an old version; please rebuild it.\n");
+               fprintf(stderr, "%s: database is corrupt or not a plocate database; please rebuild it.\n", filename_for_errors);
                exit(1);
        }
        if (hdr.version != 0 && hdr.version != 1) {
-               fprintf(stderr, "plocate.db has version %u, expected 0 or 1; please rebuild it.\n", hdr.version);
+               fprintf(stderr, "%s: has version %u, expected 0 or 1; please rebuild it.\n", filename_for_errors, hdr.version);
                exit(1);
        }
        if (hdr.version == 0) {
@@ -489,7 +489,7 @@ uint64_t do_search_file(const vector<Needle> &needles, const std::string &filena
        }
 
        IOUringEngine engine(/*slop_bytes=*/16);  // 16 slop bytes as described in turbopfor.h.
-       Corpus corpus(fd, &engine);
+       Corpus corpus(fd, filename.c_str(), &engine);
        dprintf("Corpus init done after %.1f ms.\n", 1e3 * duration<float>(steady_clock::now() - start).count());
 
        vector<TrigramDisjunction> trigram_groups;