add remove action to infobot

cdb.c

@@ -40,8 +40,10 @@ read_u32le(FILE *f)
 {
     uint8_t d[4];
 
-    fread(d, 4, 1, f);
-    return ((d[0]<< 0) |
+    if (0 == fread(d, 4, 1, f)) {
+        return 0;
+    }
+    return ((d[0] << 0) |
             (d[1] << 8) |
             (d[2] << 16) |
             (d[3] << 24));
@@ -80,24 +82,26 @@ cdb_dump(struct cdb_ctx *ctx,
         // Find out where to stop reading
         int i;
 
+        fseek(ctx->f, 0, SEEK_SET);
         ctx->hash_len = 0;
         ctx->hash_pos = 0xffffffff;
         for (i = 0; i < 256; i += 1) {
             uint32_t p;
 
-            fseek(ctx->f, i * 8, SEEK_SET);
             p = read_u32le(ctx->f);
+            read_u32le(ctx->f);
             if (p < ctx->hash_pos) {
                 ctx->hash_pos = p;
             }
         }
-        fseek(ctx->f, 256 * 8, SEEK_SET);
-    } else {
-        long where = ftell(ctx->f);
 
-        if (where >= ctx->hash_pos) {
-            return EOF;
+        ctx->entry = 256 * 8;
+        fseek(ctx->f, ctx->entry, SEEK_SET);
     } 
+    
+    // Stop if we've reached the end
+    if (ctx->entry >= ctx->hash_pos) {
+        return EOF;
     }
 
     // Read the two buffers
@@ -107,6 +111,8 @@ cdb_dump(struct cdb_ctx *ctx,
 
        *keylen = read_buf(ctx->f, klen, key, *keylen);
        *vallen = read_buf(ctx->f, vlen, val, *vallen);
+
+        ctx->entry += 4 + 4 + klen + vlen;
     }
 
     return 0;

cdbmake.c

@@ -3,6 +3,7 @@
 #include <string.h>
 #include <stdlib.h>     // XXX: remove if malloc() is gone
 #include "cdbmake.h"
+#include "dump.h"
 
 static uint32_t
 hash(char *s, size_t len)
@@ -36,7 +37,8 @@ cdbmake_init(struct cdbmake_ctx *ctx, FILE *f)
         ctx->nrecords[i] = 0;
     }
     
-    fseek(f, 256 * 8, SEEK_SET);
+    ctx->where = 256 * 8;
+    fseek(f, ctx->where, SEEK_SET);
 }
 
 void
@@ -44,7 +46,6 @@ cdbmake_add(struct cdbmake_ctx *ctx,
         char *key, size_t keylen,
         char *val, size_t vallen)
 {
-    long where = ftell(ctx->f);
     uint32_t hashval = hash(key, keylen);
     int idx = hashval % 256;
     uint32_t n = ctx->nrecords[idx];
@@ -57,13 +58,15 @@ cdbmake_add(struct cdbmake_ctx *ctx,
         return;
     }
     ctx->records[idx][n].hashval = hashval;
-    ctx->records[idx][n].offset = (uint32_t)where;
+    ctx->records[idx][n].offset = (uint32_t)ctx->where;
 
     // Write it out
     write_u32le(ctx->f, keylen);
     write_u32le(ctx->f, vallen);
     fwrite(key, 1, keylen, ctx->f);
     fwrite(val, 1, vallen, ctx->f);
+
+    ctx->where += 4 + 4 + keylen + vallen;
 }
 
 void

cdbmake.h

@@ -15,6 +15,7 @@ struct cdbmake_ctx {
     FILE *f;
     struct cdbmake_record *records[256];
     uint32_t nrecords[256];
+    long where;
 };
 
 void cdbmake_init(struct cdbmake_ctx *ctx, FILE *f);

dump.h

@@ -11,6 +11,7 @@
 #endif
 #define DUMP() DUMPf("")
 #define DUMP_d(v) DUMPf("%s = %d", #v, v)
+#define DUMP_l(v) DUMPf("%s = %ld", #v, v)
 #define DUMP_x(v) DUMPf("%s = 0x%x", #v, v)
 #define DUMP_s(v) DUMPf("%s = %s", #v, v)
 #define DUMP_c(v) DUMPf("%s = '%c' (0x%02x)", #v, v, v)

infobot.c

@@ -3,25 +3,13 @@
 #include <stdint.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <fnmatch.h>
 #include <ctype.h>
 #include <sys/time.h>
 #include <sysexits.h>
 #include "cdb.h"
 #include "cdbmake.h"
-
-/* Some things I use for debugging */
-#ifdef NODUMP
-#  define DUMPf(fmt, args...)
-#else
-#  define DUMPf(fmt, args...) fprintf(stderr, "%s:%s:%d " fmt "\n", __FILE__, __FUNCTION__, __LINE__, ##args)
-#endif
-#define DUMP() DUMPf("")
-#define DUMP_u(v) DUMPf("%s = %u", #v, v)
-#define DUMP_d(v) DUMPf("%s = %d", #v, v)
-#define DUMP_x(v) DUMPf("%s = 0x%x", #v, v)
-#define DUMP_s(v) DUMPf("%s = %s", #v, v)
-#define DUMP_c(v) DUMPf("%s = %c", #v, v)
-#define DUMP_p(v) DUMPf("%s = %p", #v, v)
+#include "dump.h"
 
 int
 usage()
@@ -115,6 +103,45 @@ list(char *filename, char *key)
     return 0;
 }
 
+static int
+setup_copy(char *infn, struct cdb_ctx *inc, FILE **inf,
+        char **outfn, struct cdbmake_ctx *outc, FILE **outf)
+{
+    static char tmpfn[8192];
+
+    *inf = fopen(infn, "rb");
+    if (! *inf) {
+        perror("Opening database");
+        return EX_NOINPUT;
+    }
+
+    snprintf(tmpfn, sizeof(tmpfn), "%s.%d", infn, getpid());
+    *outf = fopen(tmpfn, "wb");
+    if (! *outf) {
+        perror("Creating temporary database");
+        return EX_CANTCREAT;
+    }
+
+    cdb_init(inc, *inf);
+    cdbmake_init(outc, *outf);
+
+    *outfn = strdup(tmpfn);
+
+    return 0;
+}
+
+static void
+finish_copy(char *infn, struct cdb_ctx *inc, FILE **inf,
+        char *outfn, struct cdbmake_ctx *outc, FILE **outf)
+{
+    cdbmake_finalize(outc);
+    fclose(*outf);
+    fclose(*inf);
+
+    rename(outfn, infn);
+    free(outfn);
+}
+
 int
 add(char *filename, char *key, char *val)
 {
@@ -122,26 +149,14 @@ add(char *filename, char *key, char *val)
     struct cdbmake_ctx outc;
     FILE *inf;
     FILE *outf;
-    char tmpfn[8192];
+    char *outfn;
+    int ret;
 
-    // Open input file
-    inf = fopen(filename, "rb");
-    if (! inf) {
-        perror("Opening database");
-        return EX_NOINPUT;
+    ret = setup_copy(filename, &inc, &inf, &outfn, &outc, &outf);
+    if (ret) {
+        return ret;
     }
 
-    // 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;
-    }
-
-    cdb_init(&inc, inf);
-    cdbmake_init(&outc, outf);
-
     for (;;) {
         char key[8192];
         char val[8192];
@@ -154,15 +169,52 @@ add(char *filename, char *key, char *val)
         cdbmake_add(&outc, key, keylen, val, vallen);
     }
     cdbmake_add(&outc, key, strlen(key), val, strlen(val));
-    cdbmake_finalize(&outc);
 
-    fclose(outf);
-    fclose(inf);
-    rename(tmpfn, filename);
+    finish_copy(filename, &inc, &inf, outfn, &outc, &outf);
 
     return 0;
 }
 
+int
+del(char *filename, char *key, char *glob)
+{
+    size_t keylen = strlen(key);
+    struct cdb_ctx inc;
+    struct cdbmake_ctx outc;
+    FILE *inf;
+    FILE *outf;
+    char *outfn;
+    int ret;
+
+    ret = setup_copy(filename, &inc, &inf, &outfn, &outc, &outf);
+    if (ret) {
+        return ret;
+    }
+
+    for (;;) {
+        char k[8192];
+        char v[8192];
+        size_t klen = sizeof(k);
+        size_t vlen = sizeof(v) - 1;
+
+        if (EOF == cdb_dump(&inc, k, &klen, v, &vlen)) {
+            break;
+        }
+
+        v[vlen] = '\0';
+        if ((klen == keylen) &&
+                (0 == memcmp(k, key, klen)) &&
+                (0 == fnmatch(glob, v, 0))) {
+            // Skip if it matches
+        } else {
+            cdbmake_add(&outc, k, klen, v, vlen);
+        }
+    }
+
+    finish_copy(filename, &inc, &inf, outfn, &outc, &outf);
+    return 0;
+}
+
 
 enum action {
     ACT_ONE,
@@ -223,9 +275,8 @@ main(int argc, char *argv[])
             return list(filename, key);
         case ACT_ADD:
             return add(filename, key, val);
-        default:
-            fprintf(stderr, "Not yet implemented, chump %s.\n", val);
-            break;
+        case ACT_DEL:
+            return del(filename, key, val);
     }
 
     return 0;