DEV: haring: support remapping LF in contents with CR VT

Some traces may contain LF characters which are quite cumbersome to
deal with using the common tools. Given that the utility still has
access to the raw traces and knows where the delimiters are, let's
offer the possibility to remap LF characters to a different sequence.

Here we're using CR VT which will have the same visual appearance but
will remain on the same line for grep etc. This behavior is enabled by
the -l option. It's not enabled by default because it's 50% slower due
to content processing.

diff --git a/dev/haring/haring.c b/dev/haring/haring.c
index 65a735bd8b776292335031bec953e58aeeedd1fd..27e03eecfa2b994cd52101c8c0a8cdb8710bc84c 100644 (file)
--- a/dev/haring/haring.c
+++ b/dev/haring/haring.c
@@ -36,6 +36,8 @@
 #include <haproxy/ring.h>
 
 int force = 0; // force access to a different layout
+int lfremap = 0; // remap LF in traces
+
 
 /* display the message and exit with the code */
 __attribute__((noreturn)) void die(int code, const char *format, ...)
@@ -58,6 +60,7 @@ __attribute__((noreturn)) void usage(int code, const char *arg0)
            "\n"
            "options :\n"
            "  -f           : force accessing a non-matching layout for 'ring struct'\n"
+           "  -l           : replace LF in contents with CR VT\n"
            "\n"
            "", arg0);
 }
@@ -76,8 +79,8 @@ int dump_ring(struct ring *ring, size_t ofs, int flags)
        struct buffer buf;
        uint64_t msg_len = 0;
        size_t len, cnt;
-       const char *blk1, *blk2;
-       size_t len1, len2;
+       const char *blk1 = NULL, *blk2 = NULL, *p;
+       size_t len1 = 0, len2 = 0, bl;
 
        /* Explanation: the storage area in the writing process starts after
         * the end of the structure. Since the whole area is mmapped(), we know
@@ -155,12 +158,36 @@ int dump_ring(struct ring *ring, size_t ofs, int flags)
                        }
 
                        len = b_getblk_nc(&buf, &blk1, &len1, &blk2, &len2, ofs + cnt, msg_len);
-                       if (len > 0 && len1)
-                               fwrite(blk1, len1, 1, stdout);
-                       if (len > 1 && len2)
-                               fwrite(blk2, len2, 1, stdout);
-                       if (len)
-                               putchar('\n');
+                       if (!lfremap) {
+                               if (len > 0 && len1)
+                                       fwrite(blk1, len1, 1, stdout);
+                               if (len > 1 && len2)
+                                       fwrite(blk2, len2, 1, stdout);
+                       } else {
+                               while (len > 0) {
+                                       for (; len1; p++) {
+                                               p = memchr(blk1, '\n', len1);
+                                               if (!p || p > blk1) {
+                                                       bl = p ? p - blk1 : len1;
+                                                       fwrite(blk1, bl, 1, stdout);
+                                                       blk1 += bl;
+                                                       len1 -= bl;
+                                               }
+
+                                               if (p) {
+                                                       putchar('\r');
+                                                       putchar('\v');
+                                                       blk1++;
+                                                       len1--;
+                                               }
+                                       }
+                                       len--;
+                                       blk1 = blk2;
+                                       len1 = len2;
+                               }
+                       }
+
+                       putchar('\n');
 
                        ofs += cnt + msg_len;
                }
@@ -190,6 +217,8 @@ int main(int argc, char **argv)
                argc--; argv++;
                if (strcmp(argv[0], "-f") == 0)
                        force = 1;
+               else if (strcmp(argv[0], "-l") == 0)
+                       lfremap = 1;
                else if (strcmp(argv[0], "--") == 0)
                        break;
                else