Implement zstandard commit compression

1 files changed, 39 insertions, 2 deletions

diff --git a/commit.c b/commit.c
index a19aefe..12cc027 100644
--- a/commit.c
+++ b/commit.c
@@ -1,9 +1,47 @@
 #include <errno.h>
 #include <string.h>
+#include <zstd.h>
 #include "commit.h"
 
+static void nfl_commit_default(FILE* f, nflog_entry_t* store, uint32_t store_size);
+static void nfl_commit_lz4(FILE* f, nflog_entry_t* store, uint32_t store_size);
+static void nfl_commit_zstd(FILE* f, nflog_entry_t* store, uint32_t store_size);
+
+typedef void (*nflog_commit_run_table_t)(FILE* f, nflog_entry_t* store, uint32_t size);
+static const nflog_commit_run_table_t commit_run_table[] = {
+    nfl_commit_default,
+    nfl_commit_lz4,
+    nfl_commit_zstd
+};
+
 void nfl_commit_init() {
+    /* TODO */
+}
+
+static void nfl_commit_default(FILE* f, nflog_entry_t* store, uint32_t store_size) {
+    uint32_t written;
+    written = fwrite(store, 1, store_size, f);
+    ERR(written != store_size, strerror(errno));
+}
 
+static void nfl_commit_lz4(FILE* f, nflog_entry_t* store, uint32_t store_size) {
+    /* TODO */
+}
+
+static void nfl_commit_zstd(FILE* f, nflog_entry_t* store, uint32_t store_size) {
+    size_t const bufsize = ZSTD_compressBound(store_size);
+    void* buf;
+
+    ERR((buf = malloc(bufsize)), NULL);
+
+    size_t const csize = ZSTD_compress(buf, bufsize, store, store_size, 1);
+    if (ZSTD_isError(csize)) {
+        fprintf(stderr, "zstd error: %s \n", ZSTD_getErrorName(csize));
+        exit(8);
+    }
+
+    nfl_commit_default(f, buf, bufsize);
+    free(buf);
 }
 
 void nfl_commit_worker(nflog_header_t* header, nflog_entry_t* store, const char* filename) {
@@ -19,8 +57,7 @@ void nfl_commit_worker(nflog_header_t* header, nflog_entry_t* store, const char*
 
     // commit store
     uint32_t store_size = sizeof(nflog_entry_t) * header->max_n_entries;
-    written = fwrite(store, 1, store_size, f);
-    ERR(written != store_size, strerror(errno));
+    commit_run_table[header->compression_opt](f, store, store_size);
 
     // Do fsync ?
     fclose(f);