[segyio] 364/376: Don't free caller provided buffers in subtr

[Jørgen Kvalsvik]

This is an automated email from the git hooks/post-receive script.

jokva-guest pushed a commit to branch debian
in repository segyio.

commit cb94d5baa55ba2697ad0df2e4f7be12773ce8d17
Author: Jørgen Kvalsvik <jokva at statoil.com>
Date:   Wed Aug 23 13:51:23 2017 +0200

    Don't free caller provided buffers in subtr
    
    The read/write subtr functions can take a buffer for when the function
    is to be called repeatedly for speed purposes, but will allocate
    otherwise. However, the functions always tried to free this buffer, even
    if it wasn't allocated by the function.
    
    Check if the buffer was actually allocated by the functions before
    attempting to free.
    
    Tests are updated to check for this.
---
 lib/src/segy.c  | 11 +++++++----
 lib/test/segy.c | 10 ++++++----
 2 files changed, 13 insertions(+), 8 deletions(-)

diff --git a/lib/src/segy.c b/lib/src/segy.c
index 14b4570..c5750b9 100644
--- a/lib/src/segy.c
+++ b/lib/src/segy.c
@@ -1234,7 +1234,7 @@ int segy_readsubtr( segy_file* fp,
 
     const size_t readc = fread( tracebuf, sizeof( float ), elems, fp->fp );
     if( readc != elems ) {
-        free( tracebuf );
+        if( !rangebuf ) free( tracebuf );
         return SEGY_FREAD_ERROR;
     }
 
@@ -1242,7 +1242,7 @@ int segy_readsubtr( segy_file* fp,
     for( ; slicelen > 0; cur += step, --slicelen, ++buf )
         *buf = *cur;
 
-    free( tracebuf );
+    if( !rangebuf ) free( tracebuf );
     return SEGY_OK;
 }
 
@@ -1309,14 +1309,17 @@ int segy_writesubtr( segy_file* fp,
     if( readc != elems ) { free( tracebuf ); return SEGY_FREAD_ERROR; }
     /* rewind, because fread advances the file pointer */
     err = fseek( fp->fp, -elemsize, SEEK_CUR );
-    if( err != 0 ) { free( tracebuf ); return SEGY_FSEEK_ERROR; }
+    if( err != 0 ) {
+        if( !rangebuf ) free( tracebuf );
+        return SEGY_FSEEK_ERROR;
+    }
 
     float* cur = tracebuf + defstart;
     for( ; slicelen > 0; cur += step, --slicelen, ++buf )
         *cur = *buf;
 
     const size_t writec = fwrite( tracebuf, sizeof( float ), elems, fp->fp );
-    free( tracebuf );
+    if( !rangebuf ) free( tracebuf );
 
     if( writec != elems ) return SEGY_FWRITE_ERROR;
 
diff --git a/lib/test/segy.c b/lib/test/segy.c
index 6973ba8..e7de8df 100644
--- a/lib/test/segy.c
+++ b/lib/test/segy.c
@@ -115,12 +115,13 @@ static void test_read_subtr( bool mmap ) {
 
     const int format = SEGY_IBM_FLOAT_4_BYTE;
     int trace0 = 3600;
-    int trace_bsize = 50 * 4;
+    int trace_bsize = 50 * sizeof( float );
     int err = 0;
 
     if( mmap ) segy_mmap( fp );
 
     float buf[ 5 ];
+    float rangebuf[ 50 ];
     /* read a strided chunk across the middle of all traces */
     /* should read samples 3, 8, 13, 18 */
     err = segy_readsubtr( fp,
@@ -129,7 +130,7 @@ static void test_read_subtr( bool mmap ) {
                           19,       /* stop */
                           5,        /* step */
                           buf,
-                          NULL,
+                          rangebuf, // readsubtr shouldn't try to free this
                           trace0,
                           trace_bsize );
     assertTrue( err == 0, "Unable to correctly read subtrace" );
@@ -195,7 +196,7 @@ static void test_write_subtr( bool mmap ) {
     const char *file = "test-data/write-subtr.sgy";
     segy_file* fp = segy_open( file, "w+b" );
     int trace0 = 3600;
-    int trace_bsize = 50 * 4;
+    int trace_bsize = 50 * sizeof( float );
     int err = 0;
 
     const int format = SEGY_IBM_FLOAT_4_BYTE;
@@ -208,6 +209,7 @@ static void test_write_subtr( bool mmap ) {
     assertTrue( err == 0, "Error in write-subtr setup." );
 
     float buf[ 5 ];
+    float rangebuf[ 50 ];
     float out[ 5 ] = { 2.0, 2.1, 2.2, 2.3, 2.4 };
     segy_from_native( format, 5, out );
 
@@ -219,7 +221,7 @@ static void test_write_subtr( bool mmap ) {
                            19,       /* stop */
                            5,        /* step */
                            out,
-                           NULL,
+                           rangebuf, // writesubtr shouldn't try to free this
                            trace0,
                            trace_bsize );
     assertTrue( err == 0, "Unable to correctly write subtrace" );

-- 
Alioth's /usr/local/bin/git-commit-notice on /srv/git.debian.org/git/debian-science/packages/segyio.git