append action

cdbmake.c

@@ -108,7 +108,6 @@ cdbmake_finalize(struct cdbmake_ctx *ctx)
         free(buf);
     }
 
-    fclose(ctx->f);
     ctx->f = NULL;
     
     for (idx = 0; idx < 256; idx += 1) {

cdbmake.h

@@ -6,6 +6,7 @@
 #include <string.h>
 
 struct cdbmake_record {
+    FILE *f;
     uint32_t hashval;
     uint32_t offset;
 };

infobot.c

@@ -122,19 +122,18 @@ add(char *filename, char *key, char *val)
     struct cdbmake_ctx outc;
     FILE *inf;
     FILE *outf;
+    char tmpfn[8192];
 
+    // Open input file
     inf = fopen(filename, "rb");
     if (! inf) {
         perror("Opening database");
         return EX_NOINPUT;
     }
 
-    {
-        char fn[4096];
-
-        snprintf(fn, sizeof(fn), "%s.%d", filename, getpid());
-        outf = fopen(fn, "wb");
-    }
+    // Create temporary output file
+    snprintf(tmpfn, sizeof(tmpfn), "%s.%d", filename, getpid());
+    outf = fopen(tmpfn, "wb");
     if (! outf) {
         perror("Creating temporary database");
         return EX_CANTCREAT;
@@ -157,6 +156,10 @@ add(char *filename, char *key, char *val)
     cdbmake_add(&outc, key, strlen(key), val, strlen(val));
     cdbmake_finalize(&outc);
 
+    fclose(outf);
+    fclose(inf);
+    rename(tmpfn, filename);
+
     return 0;
 }