Refactor scanning through a filename block into its own function.

[plocate] / plocate.cpp

diff --git a/plocate.cpp b/plocate.cpp
index a9f624f66466c8a16c19a0f45f8365da6aaf4707..390bd21e681dcc7ad6d77458e599bb72c5424e17 100644 (file)
--- a/plocate.cpp
+++ b/plocate.cpp
@@ -10,6 +10,7 @@
 #include <sys/mman.h>
 #include <arpa/inet.h>
 #include <endian.h>
+#include <zstd.h>
 
 #include "vp4.h"
 
@@ -75,6 +76,32 @@ struct Trigram {
        uint64_t offset;
 };
 
+size_t scan_docid(const string &needle, uint32_t docid, const char *data, const uint64_t *filename_offsets, unordered_map<string, bool> *access_rx_cache)
+{
+       const char *compressed = (const char *)(data + filename_offsets[docid]);
+       size_t compressed_size = filename_offsets[docid + 1] - filename_offsets[docid];  // Allowed we have a sentinel block at the end.
+       size_t matched = 0;
+
+       string block;
+       block.resize(ZSTD_getFrameContentSize(compressed, compressed_size) + 1);
+
+       ZSTD_decompress(&block[0], block.size(), compressed, compressed_size);
+       block[block.size() - 1] = '\0';
+
+       for (const char *filename = block.data();
+                       filename != block.data() + block.size();
+                       filename += strlen(filename) + 1) {
+               if (strstr(filename, needle.c_str()) == nullptr) {
+                       continue;
+               }
+               if (has_access(filename, access_rx_cache)) {
+                       ++matched;
+                       printf("%s\n", filename);
+               }
+       }
+       return matched;
+}
+
 void do_search_file(const string &needle, const char *filename)
 {
        int fd = open(filename, O_RDONLY);
@@ -176,14 +203,7 @@ void do_search_file(const string &needle, const char *filename)
        const uint64_t *filename_offsets = (const uint64_t *)(data + filename_index_offset);
        int matched = 0;
        for (uint32_t docid : in1) {
-               const char *filename = (const char *)(data + filename_offsets[docid]);
-               if (strstr(filename, needle.c_str()) == nullptr) {
-                       continue;
-               }
-               if (has_access(filename, &access_rx_cache)) {
-                       ++matched;
-                       printf("%s\n", filename);
-               }
+               matched += scan_docid(needle, docid, data, filename_offsets, &access_rx_cache);
        }
        end = steady_clock::now();
        dprintf("Done in %.1f ms, found %d matches.\n",