Make create_EXIF allocate enough memory

The create_EXIF method crashes if over 1K bytes exif header
is passed because only 1K byte is allocated for exif header.
It is hard to calcurate exact nessesary size for editing the
exif header dynamically, so this value is changed to the
mamixmum size of exif, 64K.

Change-Id: Ia2c8481da5130f02ec8f1c63ece9aa4289b1ad5f

1 files changed, 16 insertions, 5 deletions

diff --git a/exif.c b/exif.c
index 3747bf6..7efb6fe 100644
--- a/exif.c
+++ b/exif.c
@@ -1168,12 +1168,8 @@ char* formatStr(int format) {
 // Create minimal exif header - just date and thumbnail pointers,
 // so that date and thumbnail may be filled later.
 //--------------------------------------------------------------------------
-void create_EXIF(ExifElement_t* elements, int exifTagCount, int gpsTagCount)
+static void create_EXIF_internal(ExifElement_t* elements, int exifTagCount, int gpsTagCount, char* Buffer)
 {
-    // TODO: We need to dynamically allocate this buffer and resize it when
-    // necessary while writing so we don't do a buffer overflow.
-    char Buffer[1024];
-
     unsigned short NumEntries;
     int DataWriteIndex;
     int DirIndex;
@@ -1384,6 +1380,21 @@ void create_EXIF(ExifElement_t* elements, int exifTagCount, int gpsTagCount)
     }
 }
 
+void create_EXIF(ExifElement_t* elements, int exifTagCount, int gpsTagCount)
+{
+    // It is hard to calculate exact necessary size for editing the exif
+    // header dynamically, so we are using the maximum size of EXIF, 64K
+    const int EXIF_MAX_SIZE = 1024*64;
+    char* Buffer = malloc(EXIF_MAX_SIZE);
+
+    if (Buffer != NULL) {
+        create_EXIF_internal(elements, exifTagCount, gpsTagCount, Buffer);
+        free(Buffer);
+    } else {
+        ErrFatal("Could not allocate memory");
+    }
+}
+
 //--------------------------------------------------------------------------
 // Cler the rotation tag in the exif header to 1.
 //--------------------------------------------------------------------------