Fix non-matching packet context wrt last packet event read

[babeltrace.git] / formats / ctf / ctf.c

diff --git a/formats/ctf/ctf.c b/formats/ctf/ctf.c
index 021abf88891c6c0ff7dc62beedde1444a162f061..f078735c3ea9fd5307c46333b28b2c473867a7e1 100644 (file)
--- a/formats/ctf/ctf.c
+++ b/formats/ctf/ctf.c
@@ -125,8 +125,11 @@ int ctf_read_event(struct stream_pos *ppos, struct ctf_stream *stream)
        uint64_t id = 0;
        int ret;
 
+       ctf_pos_get_event(pos);
+
        if (pos->offset == EOF)
                return EOF;
+       assert(pos->offset < pos->content_size);
 
        /* Read event header */
        if (stream->stream_event_header) {
@@ -390,8 +393,11 @@ void ctf_move_pos_slow(struct ctf_stream_pos *pos, size_t offset, int whence)
                assert(off >= 0);
                pos->offset = 0;
        } else {
+       read_next_packet:
                switch (whence) {
                case SEEK_CUR:
+                       if (pos->offset == EOF)
+                               return;
                        /* The reader will expect us to skip padding */
                        assert(pos->offset + offset == pos->content_size);
                        ++pos->cur_index;
@@ -415,9 +421,14 @@ void ctf_move_pos_slow(struct ctf_stream_pos *pos, size_t offset, int whence)
                file_stream->parent.timestamp = index->timestamp_begin;
                pos->content_size = index->content_size;
                pos->packet_size = index->packet_size;
-               if (index->data_offset < index->content_size)
+               if (index->data_offset < index->content_size) {
                        pos->offset = 0;        /* will read headers */
-               else {
+               } else if (index->data_offset == index->content_size) {
+                       /* empty packet */
+                       pos->offset = index->data_offset;
+                       offset = 0;
+                       goto read_next_packet;
+               } else {
                        pos->offset = EOF;
                        return;
                }
@@ -470,6 +481,32 @@ end:
        return ret;
 }
 
+/*
+ * Returns 0 on success, -1 on error.
+ */
+static
+int check_version(unsigned int major, unsigned int minor)
+{
+       switch (major) {
+       case 1:
+               switch (minor) {
+               case 8:
+                       return 0;
+               default:
+                       goto warning;
+               }
+       default:
+               goto warning;
+               
+       }
+
+       /* eventually return an error instead of warning */
+warning:
+       fprintf(stdout, "[warning] Unsupported CTF specification version %u.%u. Trying anyway.\n",
+               major, minor);
+       return 0;
+}
+
 static
 int ctf_open_trace_metadata_packet_read(struct ctf_trace *td, FILE *in,
                                        FILE *out)
@@ -506,6 +543,8 @@ int ctf_open_trace_metadata_packet_read(struct ctf_trace *td, FILE *in,
                        header.checksum_scheme);
                return -EINVAL;
        }
+       if (check_version(header.major, header.minor) < 0)
+               return -EINVAL;
        if (!CTF_TRACE_FIELD_IS_SET(td, uuid)) {
                memcpy(td->uuid, header.uuid, sizeof(header.uuid));
                CTF_TRACE_SET_FIELD(td, uuid);
@@ -540,10 +579,19 @@ int ctf_open_trace_metadata_packet_read(struct ctf_trace *td, FILE *in,
                toread -= readlen;
                if (!toread) {
                        ret = 0;        /* continue reading next packet */
-                       break;
+                       goto read_padding;
                }
        }
        return ret;
+
+read_padding:
+       toread = (header.packet_size - header.content_size) / CHAR_BIT;
+       ret = fseek(in, toread, SEEK_CUR);
+       if (ret < 0) {
+               fprintf(stdout, "[warning] Missing padding at end of file\n");
+               ret = 0;
+       }
+       return ret;
 }
 
 static
@@ -613,16 +661,19 @@ int ctf_open_trace_metadata_read(struct ctf_trace *td)
                if (ret)
                        goto end_packet_read;
        } else {
-               char buf[sizeof("/* TSDL")];    /* Includes \0 */
-               ssize_t readlen;
+               unsigned int major, minor;
+               ssize_t nr_items;
 
                td->byte_order = BYTE_ORDER;
 
-               /* Check text-only metadata header */
-               buf[sizeof("/* TSDL") - 1] = '\0';
-               readlen = fread(buf, sizeof("/* TSDL") - 1, 1, fp);
-               if (readlen < 1 || strcmp(buf, "/* TSDL") != 0)
-                       fprintf(stdout, "[warning] Missing \"/* TSDL\" header for text-only metadata.\n");
+               /* Check text-only metadata header and version */
+               nr_items = fscanf(fp, "/* CTF %u.%u", &major, &minor);
+               if (nr_items < 2)
+                       fprintf(stdout, "[warning] Ill-shapen or missing \"/* CTF x.y\" header for text-only metadata.\n");
+               if (check_version(major, minor) < 0) {
+                       ret = -EINVAL;
+                       goto end_packet_read;
+               }
                rewind(fp);
        }