diff options
Diffstat (limited to 'generic/tkImgGIF.c')
| -rw-r--r-- | generic/tkImgGIF.c | 55 |
1 files changed, 33 insertions, 22 deletions
diff --git a/generic/tkImgGIF.c b/generic/tkImgGIF.c index 8dbca04..3a4246a 100644 --- a/generic/tkImgGIF.c +++ b/generic/tkImgGIF.c @@ -29,7 +29,7 @@ * | provided "as is" without express or implied warranty. | * +-------------------------------------------------------------------+ * - * RCS: @(#) $Id: tkImgGIF.c,v 1.24.2.1 2004/07/27 20:31:02 das Exp $ + * RCS: @(#) $Id: tkImgGIF.c,v 1.24.2.2 2005/06/20 10:28:00 dkf Exp $ */ /* @@ -55,6 +55,7 @@ typedef struct mFile { unsigned char *data; /* mmencoded source string */ + int length; /* Length of string in bytes */ int c; /* bits left over from previous character */ int state; /* decoder state (0-4 or GIF_DONE) */ } MFile; @@ -173,7 +174,7 @@ static int Mread _ANSI_ARGS_((unsigned char *dst, size_t size, static int Mgetc _ANSI_ARGS_((MFile *handle)); static int char64 _ANSI_ARGS_((int c)); static void mInit _ANSI_ARGS_((unsigned char *string, - MFile *handle)); + int length, MFile *handle)); /* @@ -552,7 +553,7 @@ StringMatchGIF(dataObj, format, widthPtr, heightPtr, interp) /* * Try interpreting the data as Base64 encoded */ - mInit((unsigned char *) data, &handle); + mInit((unsigned char *) data, length, &handle); got = Mread(header, 10, 1, &handle); if (got != 10 || ((strncmp(GIF87a, (char *) header, 6) != 0) @@ -599,7 +600,7 @@ StringReadGIF(interp, dataObj, format, imageHandle, int width, height; /* image to copy */ int srcX, srcY; { - int result; + int result, length; MFile handle; ThreadSpecificData *tsdPtr = (ThreadSpecificData *) Tcl_GetThreadData(&dataKey, sizeof(ThreadSpecificData)); @@ -609,14 +610,14 @@ StringReadGIF(interp, dataObj, format, imageHandle, /* * Check whether the data is Base64 encoded */ - data = (char *) Tcl_GetByteArrayFromObj(dataObj, NULL); + data = (char *) Tcl_GetByteArrayFromObj(dataObj, &length); if ((strncmp(GIF87a, data, 6) != 0) && (strncmp(GIF89a, data, 6) != 0)) { - mInit((unsigned char *)data, &handle); + mInit((unsigned char *)data, length, &handle); tsdPtr->fromData = 1; dataSrc = (Tcl_Channel) &handle; } else { tsdPtr->fromData = 2; - mInit((unsigned char *)data, &handle); + mInit((unsigned char *)data, length, &handle); dataSrc = (Tcl_Channel) &handle; } result = FileReadGIF(interp, dataSrc, "inline data", @@ -1123,13 +1124,15 @@ GetCode(chan, code_size, flag) */ static void -mInit(string, handle) - unsigned char *string; /* string containing initial mmencoded data */ - MFile *handle; /* mmdecode "file" handle */ +mInit(string, length, handle) + unsigned char *string; /* string containing initial mmencoded data */ + int length; /* Length of string */ + MFile *handle; /* mmdecode "file" handle */ { - handle->data = string; - handle->state = 0; - handle->c = 0; + handle->data = string; + handle->length = length; + handle->state = 0; + handle->c = 0; } /* @@ -1152,18 +1155,18 @@ mInit(string, handle) static int Mread(dst, chunkSize, numChunks, handle) - unsigned char *dst; /* where to put the result */ - size_t chunkSize; /* size of each transfer */ - size_t numChunks; /* number of chunks */ - MFile *handle; /* mmdecode "file" handle */ + unsigned char *dst; /* where to put the result */ + size_t chunkSize; /* size of each transfer */ + size_t numChunks; /* number of chunks */ + MFile *handle; /* mmdecode "file" handle */ { - register int i, c; - int count = chunkSize * numChunks; + register int i, c; + int count = chunkSize * numChunks; - for(i=0; i<count && (c=Mgetc(handle)) != GIF_DONE; i++) { + for(i=0; i<count && (c=Mgetc(handle)) != GIF_DONE; i++) { *dst++ = c; - } - return i; + } + return i; } /* @@ -1201,6 +1204,10 @@ Mgetc(handle) } do { + if (handle->length-- <= 0) { + handle->state = GIF_DONE; + return GIF_DONE; + } c = char64(*handle->data); handle->data++; } while (c == GIF_SPACE); @@ -1315,8 +1322,12 @@ Fread(dst, hunk, count, chan) return Mread(dst, hunk, count, (MFile *) chan); case 2: handle = (MFile *) chan; + if (handle->length <= 0 || (size_t)handle->length < (size_t) (hunk * count)) { + return -1; + } memcpy((VOID *)dst, (VOID *) handle->data, (size_t) (hunk * count)); handle->data += hunk * count; + handle->length -= hunk * count; return (int)(hunk * count); default: return Tcl_Read(chan, (char *) dst, (int) (hunk * count)); |