diff options
Diffstat (limited to 'lib/libpnm1.c')
-rw-r--r-- | lib/libpnm1.c | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/lib/libpnm1.c b/lib/libpnm1.c index 536e5dc4..29fee13a 100644 --- a/lib/libpnm1.c +++ b/lib/libpnm1.c @@ -72,10 +72,13 @@ validateComputableSize(unsigned int const cols, you expect. That failed expectation can be disastrous if you use it to allocate memory. + It is very normal to allocate space for a pixel row, so we make sure + the size of a pixel row, in bytes, can be represented by an 'int'. + A common operation is adding 1 or 2 to the highest row or column number in the image, so we make sure that's possible. -----------------------------------------------------------------------------*/ - if (cols > INT_MAX - 2) + if (cols > INT_MAX/(sizeof(pixval) * 3) || cols > INT_MAX - 2) pm_error("image width (%u) too large to be processed", cols); if (rows > INT_MAX - 2) pm_error("image height (%u) too large to be processed", rows); @@ -178,10 +181,10 @@ readpbmrow(FILE * const fileP, jmp_buf * origJmpbufP; bit * bitrow; - bitrow = pbm_allocrow(cols); + bitrow = pbm_allocrow_packed(cols); if (setjmp(jmpbuf) != 0) { - pbm_freerow(bitrow); + pbm_freerow_packed(bitrow); pm_setjmpbuf(origJmpbufP); pm_longjmp(); } else { @@ -189,11 +192,14 @@ readpbmrow(FILE * const fileP, pm_setjmpbufsave(&jmpbuf, &origJmpbufP); - pbm_readpbmrow(fileP, bitrow, cols, format); - - for (col = 0; col < cols; ++col) - PNM_ASSIGN1(xelrow[col], bitrow[col] == PBM_BLACK ? 0 : maxval); + pbm_readpbmrow_packed(fileP, bitrow, cols, format); + for (col = 0; col < cols; ++col) { + pixval const g = + ((bitrow[col/8] >> (7 - col%8)) & 0x1) == PBM_WHITE ? + maxval : 0; + PNM_ASSIGN1(xelrow[col], g); + } pm_setjmpbuf(origJmpbufP); } pbm_freerow(bitrow); |