Eliminate unnecessary NULL checks before free()

This programming practice (which exists in other code bases as well) is a by-product of having used early C compilers that did not properly handle free(NULL). All modern compilers should properly handle that. Fixes mozilla#398
Jehan · Jan 7, 2020 · fdf8903 · fdf8903
1 parent 166e342
commit fdf8903
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Showing 4 changed files with 47 additions and 51 deletions.
diff --git a/tjbench.c b/tjbench.c
@@ -304,8  304,8 @@ static int decomp(unsigned char *srcBuf, unsigned char **jpegBuf,
 bailout:
   if (file) fclose(file);
   if (handle) tjDestroy(handle);
-  if (dstBuf && dstBufAlloc) free(dstBuf);
-  if (yuvBuf) free(yuvBuf);
   if (dstBufAlloc) free(dstBuf);
   free(yuvBuf);
   return retval;
 }
 
@@ -502,18  502,16 @@ static int fullTest(unsigned char *srcBuf, int w, int h, int subsamp,
   }
 
 bailout:
-  if (file) { fclose(file);  file = NULL; }
   if (file) fclose(file);
   if (jpegBuf) {
-    for (i = 0; i < ntilesw * ntilesh; i  ) {
     for (i = 0; i < ntilesw * ntilesh; i  )
       if (jpegBuf[i]) tjFree(jpegBuf[i]);
-      jpegBuf[i] = NULL;
-    }
-    free(jpegBuf);  jpegBuf = NULL;
   }
-  if (yuvBuf) { free(yuvBuf);  yuvBuf = NULL; }
-  if (jpegSize) { free(jpegSize);  jpegSize = NULL; }
-  if (tmpBuf) { free(tmpBuf);  tmpBuf = NULL; }
-  if (handle) { tjDestroy(handle);  handle = NULL; }
   free(jpegBuf);
   free(yuvBuf);
   free(jpegSize);
   free(tmpBuf);
   if (handle) tjDestroy(handle);
   return retval;
 }
 
@@ -720,23  718,21 @@ static int decompTest(char *fileName)
       jpegBuf[i] = NULL;
     }
     free(jpegBuf);  jpegBuf = NULL;
-    if (jpegSize) { free(jpegSize);  jpegSize = NULL; }
     free(jpegSize);  jpegSize = NULL;
 
     if (tilew == w && tileh == h) break;
   }
 
 bailout:
-  if (file) { fclose(file);  file = NULL; }
   if (file) fclose(file);
   if (jpegBuf) {
-    for (i = 0; i < ntilesw * ntilesh; i  ) {
     for (i = 0; i < ntilesw * ntilesh; i  )
       if (jpegBuf[i]) tjFree(jpegBuf[i]);
-      jpegBuf[i] = NULL;
-    }
-    free(jpegBuf);  jpegBuf = NULL;
   }
-  if (jpegSize) { free(jpegSize);  jpegSize = NULL; }
-  if (srcBuf) { free(srcBuf);  srcBuf = NULL; }
-  if (t) { free(t);  t = NULL; }
   free(jpegBuf);
   free(jpegSize);
   free(srcBuf);
   free(t);
   if (handle) { tjDestroy(handle);  handle = NULL; }
   return retval;
 }

diff --git a/tjunittest.c b/tjunittest.c
@@ -410,8  410,8 @@ static void compTest(tjhandle handle, unsigned char **dstBuf,
   printf("Done.\n  Result in %s\n", tempStr);
 
 bailout:
-  if (yuvBuf) free(yuvBuf);
-  if (srcBuf) free(srcBuf);
   free(yuvBuf);
   free(srcBuf);
 }
 
 
@@ -478,8  478,8 @@ static void _decompTest(tjhandle handle, unsigned char *jpegBuf,
   printf("\n");
 
 bailout:
-  if (yuvBuf) free(yuvBuf);
-  if (dstBuf) free(dstBuf);
   free(yuvBuf);
   free(dstBuf);
 }
 
 
@@ -665,7  665,7 @@ static void bufSizeTest(void)
   printf("Done.      \n");
 
 bailout:
-  if (srcBuf) free(srcBuf);
   free(srcBuf);
   if (dstBuf) tjFree(dstBuf);
   if (handle) tjDestroy(handle);
 }

diff --git a/turbojpeg-jni.c b/turbojpeg-jni.c
@@ -1232,9  1232,9 @@ JNIEXPORT jintArray JNICALL Java_org_libjpegturbo_turbojpeg_TJTransformer_transf
     free(dstBufs);
   }
   SAFE_RELEASE(jsrcBuf, jpegBuf);
-  if (jdstBufs) free(jdstBufs);
-  if (dstSizes) free(dstSizes);
-  if (t) free(t);
   free(jdstBufs);
   free(dstSizes);
   free(t);
   return jdstSizes;
 }
 

diff --git a/turbojpeg.c b/turbojpeg.c
@@ -432,7  432,7 @@ DLLEXPORT int tjDestroy(tjhandle handle)
 
 DLLEXPORT void tjFree(unsigned char *buf)
 {
-  if (buf) free(buf);
   free(buf);
 }
 
 
@@ -462,7  462,7 @@ static tjhandle _tjInitCompress(tjinstance *this)
 
   if (setjmp(this->jerr.setjmp_buffer)) {
     /* If we get here, the JPEG code has signaled an error. */
-    if (this) free(this);
     free(this);
     return NULL;
   }
 
@@ -692,7  692,7 @@ DLLEXPORT int tjCompress2(tjhandle handle, const unsigned char *srcBuf,
 
 bailout:
   if (cinfo->global_state > CSTATE_START) jpeg_abort_compress(cinfo);
-  if (row_pointer) free(row_pointer);
   free(row_pointer);
   if (this->jerr.warning) retval = -1;
   this->jerr.stopOnWarning = FALSE;
   return retval;
@@ -866,13  866,13 @@ DLLEXPORT int tjEncodeYUVPlanes(tjhandle handle, const unsigned char *srcBuf,
 
 bailout:
   if (cinfo->global_state > CSTATE_START) jpeg_abort_compress(cinfo);
-  if (row_pointer) free(row_pointer);
   free(row_pointer);
   for (i = 0; i < MAX_COMPONENTS; i  ) {
-    if (tmpbuf[i] != NULL) free(tmpbuf[i]);
-    if (_tmpbuf[i] != NULL) free(_tmpbuf[i]);
-    if (tmpbuf2[i] != NULL) free(tmpbuf2[i]);
-    if (_tmpbuf2[i] != NULL) free(_tmpbuf2[i]);
-    if (outbuf[i] != NULL) free(outbuf[i]);
     free(tmpbuf[i]);
     free(_tmpbuf[i]);
     free(tmpbuf2[i]);
     free(_tmpbuf2[i]);
     free(outbuf[i]);
   }
   if (this->jerr.warning) retval = -1;
   this->jerr.stopOnWarning = FALSE;
@@ -1062,10  1062,10 @@ DLLEXPORT int tjCompressFromYUVPlanes(tjhandle handle,
 bailout:
   if (cinfo->global_state > CSTATE_START) jpeg_abort_compress(cinfo);
   for (i = 0; i < MAX_COMPONENTS; i  ) {
-    if (tmpbuf[i]) free(tmpbuf[i]);
-    if (inbuf[i]) free(inbuf[i]);
     free(tmpbuf[i]);
     free(inbuf[i]);
   }
-  if (_tmpbuf) free(_tmpbuf);
   free(_tmpbuf);
   if (this->jerr.warning) retval = -1;
   this->jerr.stopOnWarning = FALSE;
   return retval;
@@ -1130,7  1130,7 @@ static tjhandle _tjInitDecompress(tjinstance *this)
 
   if (setjmp(this->jerr.setjmp_buffer)) {
     /* If we get here, the JPEG code has signaled an error. */
-    if (this) free(this);
     free(this);
     return NULL;
   }
 
@@ -1313,7  1313,7 @@ DLLEXPORT int tjDecompress2(tjhandle handle, const unsigned char *jpegBuf,
 
 bailout:
   if (dinfo->global_state > DSTATE_START) jpeg_abort_decompress(dinfo);
-  if (row_pointer) free(row_pointer);
   free(row_pointer);
   if (this->jerr.warning) retval = -1;
   this->jerr.stopOnWarning = FALSE;
   return retval;
@@ -1519,11  1519,11 @@ DLLEXPORT int tjDecodeYUVPlanes(tjhandle handle,
 
 bailout:
   if (dinfo->global_state > DSTATE_START) jpeg_abort_decompress(dinfo);
-  if (row_pointer) free(row_pointer);
   free(row_pointer);
   for (i = 0; i < MAX_COMPONENTS; i  ) {
-    if (tmpbuf[i] != NULL) free(tmpbuf[i]);
-    if (_tmpbuf[i] != NULL) free(_tmpbuf[i]);
-    if (inbuf[i] != NULL) free(inbuf[i]);
     free(tmpbuf[i]);
     free(_tmpbuf[i]);
     free(inbuf[i]);
   }
   if (this->jerr.warning) retval = -1;
   this->jerr.stopOnWarning = FALSE;
@@ -1731,10  1731,10 @@ DLLEXPORT int tjDecompressToYUVPlanes(tjhandle handle,
 bailout:
   if (dinfo->global_state > DSTATE_START) jpeg_abort_decompress(dinfo);
   for (i = 0; i < MAX_COMPONENTS; i  ) {
-    if (tmpbuf[i]) free(tmpbuf[i]);
-    if (outbuf[i]) free(outbuf[i]);
     free(tmpbuf[i]);
     free(outbuf[i]);
   }
-  if (_tmpbuf) free(_tmpbuf);
   free(_tmpbuf);
   if (this->jerr.warning) retval = -1;
   this->jerr.stopOnWarning = FALSE;
   return retval;
@@ -1979,7  1979,7 @@ DLLEXPORT int tjTransform(tjhandle handle, const unsigned char *jpegBuf,
 bailout:
   if (cinfo->global_state > CSTATE_START) jpeg_abort_compress(cinfo);
   if (dinfo->global_state > DSTATE_START) jpeg_abort_decompress(dinfo);
-  if (xinfo) free(xinfo);
   free(xinfo);
   if (this->jerr.warning) retval = -1;
   this->jerr.stopOnWarning = FALSE;
   return retval;
@@ -2074,7  2074,7 @@ DLLEXPORT unsigned char *tjLoadImage(const char *filename, int *width,
 bailout:
   if (handle) tjDestroy(handle);
   if (file) fclose(file);
-  if (retval < 0 && dstBuf) { free(dstBuf);  dstBuf = NULL; }
   if (retval < 0) { free(dstBuf);  dstBuf = NULL; }
   return dstBuf;
 }