Mercurial > sdl-ios-xcode
changeset 3310:b907e83deb88
Fixed crash with right side up BMP files
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 26 Sep 2009 06:21:36 +0000 |
parents | e1f161215f72 |
children | 0679e03ef8fa |
files | src/video/SDL_bmp.c |
diffstat | 1 files changed, 36 insertions(+), 21 deletions(-) [+] |
line wrap: on
line diff
--- a/src/video/SDL_bmp.c Sat Sep 26 03:58:35 2009 +0000 +++ b/src/video/SDL_bmp.c Sat Sep 26 06:21:36 2009 +0000 @@ -49,7 +49,7 @@ SDL_Surface * SDL_LoadBMP_RW(SDL_RWops * src, int freesrc) { - int was_error; + SDL_bool was_error; long fp_offset; int bmpPitch; int i, pad; @@ -59,6 +59,8 @@ Uint32 Bmask; SDL_Palette *palette; Uint8 *bits; + Uint8 *top, *end; + SDL_bool topDown; int ExpandBMP; /* The Win32 BMP file header (14 bytes) */ @@ -83,9 +85,9 @@ /* Make sure we are passed a valid data source */ surface = NULL; - was_error = 0; + was_error = SDL_FALSE; if (src == NULL) { - was_error = 1; + was_error = SDL_TRUE; goto done; } @@ -94,12 +96,12 @@ SDL_ClearError(); if (SDL_RWread(src, magic, 1, 2) != 2) { SDL_Error(SDL_EFREAD); - was_error = 1; + was_error = SDL_TRUE; goto done; } if (SDL_strncmp(magic, "BM", 2) != 0) { SDL_SetError("File is not a Windows BMP file"); - was_error = 1; + was_error = SDL_TRUE; goto done; } bfSize = SDL_ReadLE32(src); @@ -132,10 +134,16 @@ biClrUsed = SDL_ReadLE32(src); biClrImportant = SDL_ReadLE32(src); } + if (biHeight < 0) { + topDown = SDL_TRUE; + biHeight = -biHeight; + } else { + topDown = SDL_FALSE; + } /* Check for read error */ if (SDL_strcmp(SDL_GetError(), "") != 0) { - was_error = 1; + was_error = SDL_TRUE; goto done; } @@ -199,7 +207,7 @@ break; default: SDL_SetError("Compressed BMP files not supported"); - was_error = 1; + was_error = SDL_TRUE; goto done; } @@ -208,7 +216,7 @@ SDL_CreateRGBSurface(0, biWidth, biHeight, biBitCount, Rmask, Gmask, Bmask, 0); if (surface == NULL) { - was_error = 1; + was_error = SDL_TRUE; goto done; } @@ -226,7 +234,7 @@ sizeof(*palette->colors)); if (!palette->colors) { SDL_OutOfMemory(); - was_error = 1; + was_error = SDL_TRUE; goto done; } } else if ((int) biClrUsed < palette->ncolors) { @@ -252,10 +260,11 @@ /* Read the surface pixels. Note that the bmp image is upside down */ if (SDL_RWseek(src, fp_offset + bfOffBits, RW_SEEK_SET) < 0) { SDL_Error(SDL_EFSEEK); - was_error = 1; + was_error = SDL_TRUE; goto done; } - bits = (Uint8 *) surface->pixels + (surface->h * surface->pitch); + top = (Uint8 *)surface->pixels; + end = (Uint8 *)surface->pixels+(surface->h*surface->pitch); switch (ExpandBMP) { case 1: bmpPitch = (biWidth + 7) >> 3; @@ -269,19 +278,22 @@ pad = ((surface->pitch % 4) ? (4 - (surface->pitch % 4)) : 0); break; } - while (bits > (Uint8 *) surface->pixels) { - bits -= surface->pitch; + if (topDown) { + bits = top; + } else { + bits = end - surface->pitch; + } + while (bits >= top && bits < end) { switch (ExpandBMP) { case 1: - case 4: - { + case 4:{ Uint8 pixel = 0; int shift = (8 - ExpandBMP); for (i = 0; i < surface->w; ++i) { if (i % (8 / ExpandBMP) == 0) { if (!SDL_RWread(src, &pixel, 1, 1)) { SDL_SetError("Error reading from BMP"); - was_error = 1; + was_error = SDL_TRUE; goto done; } } @@ -295,7 +307,7 @@ if (SDL_RWread(src, bits, 1, surface->pitch) != surface->pitch) { SDL_Error(SDL_EFREAD); - was_error = 1; + was_error = SDL_TRUE; goto done; } #if SDL_BYTEORDER == SDL_BIG_ENDIAN @@ -303,16 +315,14 @@ case has already been taken care of above. */ switch (biBitCount) { case 15: - case 16: - { + case 16:{ Uint16 *pix = (Uint16 *) bits; for (i = 0; i < surface->w; i++) pix[i] = SDL_Swap16(pix[i]); break; } - case 32: - { + case 32:{ Uint32 *pix = (Uint32 *) bits; for (i = 0; i < surface->w; i++) pix[i] = SDL_Swap32(pix[i]); @@ -329,6 +339,11 @@ SDL_RWread(src, &padbyte, 1, 1); } } + if (topDown) { + bits += surface->pitch; + } else { + bits -= surface->pitch; + } } done: if (was_error) {