fix a bug that caused formatters to overwrite header payloads if

there is more than one in a record spanning more than one chunk

src/format.c

@@ -53,7 +53,7 @@ typedef struct compiled_fmt_t {
 } compiled_fmt_t;
 
 static struct vsb payload_storage, * const payload = &payload_storage,
-    *i_arg,  *scratch;
+    *i_arg,  *scratch, hdr_storage, * const hdr_sb = &hdr_storage;
 
 static char empty[] = "";
 static char hit[] = "hit";
@@ -137,25 +137,33 @@ get_hdr(const tx_t *tx, enum VSL_tag_e tag, const char *hdr)
 
     CHECK_OBJ_NOTNULL(tx, TX_MAGIC);
     VSTAILQ_FOREACH(rec, &tx->recs, reclist) {
-        char *c;
+        char *c, *h;
 
         CHECK_OBJ_NOTNULL(rec, RECORD_MAGIC);
         assert(OCCUPIED(rec));
         if (rec->tag != tag)
             continue;
         c = get_payload(rec);
-        while (isspace(*c))
-            c++;
-        if (strncasecmp(c, hdr, strlen(hdr)) != 0)
+        h = c;
+        while (isspace(*h))
+            h++;
+        if (strncasecmp(h, hdr, strlen(hdr)) != 0)
             continue;
-        c += strlen(hdr);
-        while (isspace(*c))
-            c++;
-        if (*c++ != ':')
+        h += strlen(hdr);
+        while (isspace(*h))
+            h++;
+        if (*h++ != ':')
             continue;
-        while (isspace(*c))
-            c++;
-        hdr_payload = c;
+        while (isspace(*h))
+            h++;
+        if (rec->len <= config.chunk_size)
+            hdr_payload = h;
+        else {
+            VSB_clear(hdr_sb);
+            VSB_bcpy(hdr_sb, h, rec->len - (h - c));
+            VSB_finish(hdr_sb);
+            hdr_payload = VSB_data(hdr_sb);
+        }
     }
     return hdr_payload;
 }
@@ -1212,6 +1220,7 @@ int
 FMT_Init(char *err)
 {
     AN(VSB_new(payload, NULL, config.max_reclen + 1, VSB_FIXEDLEN));
+    AN(VSB_new(hdr_sb, NULL, config.max_reclen + 1, VSB_FIXEDLEN));
     i_arg = VSB_new_auto();
     AN(i_arg);
     scratch = VSB_new_auto();

src/test/test_format.c

@@ -210,8 +210,8 @@ static const char
 {
     tx_t tx;
     rec_t recs[NRECORDS];
-    chunk_t c[NRECORDS];
-    char *hdr;
+    chunk_t c[NRECORDS], *c1, *c2;
+    char *hdr, *exp;
 
     printf("... testing get_hdr()\n");
 
@@ -252,6 +252,45 @@ static const char
     MAN(hdr);
     MASSERT(strcmp(hdr, "wilco") == 0);
 
+    /* Different headers after the matching header */
+    hdr = get_hdr(&tx, SLT_ReqHeader, "Bar");
+    MAN(hdr);
+    MASSERT(strcmp(hdr, "baz") == 0);
+
+    /* Different headers spanning more than one chunk after the matching
+     * header */
+    c1 = (chunk_t *) calloc(1, sizeof(chunk_t));
+    MAN(c1);
+    c1->magic = CHUNK_MAGIC;
+    c1->data = (char *) calloc(1, config.chunk_size);
+    MAN(c1->data);
+    c1->occupied = 1;
+    VSTAILQ_INSERT_TAIL(&recs[NRECORDS - 2].chunks, c1, chunklist);
+    recs[NRECORDS - 2].len = config.chunk_size * 2;
+    strcpy(c[NRECORDS - 2].data, "Garply: ");
+    memset(c[NRECORDS - 2].data + strlen("Garply : ") - 1, 'x',
+           config.chunk_size - strlen("Garply: "));
+    memset(c1->data, 'x', config.chunk_size);
+    c2 = (chunk_t *) calloc(1, sizeof(chunk_t));
+    MAN(c2);
+    c2->magic = CHUNK_MAGIC;
+    c2->data = (char *) calloc(1, config.chunk_size);
+    MAN(c2->data);
+    c2->occupied = 1;
+    VSTAILQ_INSERT_TAIL(&recs[NRECORDS - 1].chunks, c2, chunklist);
+    recs[NRECORDS - 1].len = config.chunk_size * 2;
+    strcpy(c[NRECORDS - 1].data, "Xyzzy: ");
+    memset(c[NRECORDS - 1].data + strlen("Xyzzy : ") - 1, 'y',
+           config.chunk_size - strlen("Xyzzy: "));
+    memset(c2->data, 'y', config.chunk_size);
+    hdr = get_hdr(&tx, SLT_ReqHeader, "Garply");
+    MAN(hdr);
+    int len = 2 * config.chunk_size - strlen("Garply: ");
+    exp = (char *) malloc(len);
+    MAN(exp);
+    memset(exp, 'x', len);
+    MASSERT(memcmp(hdr, exp, len) == 0);
+
     /* Record not found */
     recs[NRECORDS / 2].tag = SLT_RespHeader;
     recs[NRECORDS - 1].tag = SLT_RespHeader;