62       #define png_jmpbuf(png_ptr) ((png_ptr)->jmpbuf)  argument
69   png_struct  *png_ptr;  in PetscDrawImageSavePNG()  local
80   png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);  in PetscDrawImageSavePNG()
81   PetscCheck(png_ptr, PETSC_COMM_SELF, PETSC_ERR_LIB, "Cannot create PNG context");  in PetscDrawImageSavePNG()
82   info_ptr = png_create_info_struct(png_ptr);  in PetscDrawImageSavePNG()
87   if (setjmp(png_jmpbuf(png_ptr))) {  in PetscDrawImageSavePNG()
88     png_destroy_write_struct(&png_ptr, &info_ptr);  in PetscDrawImageSavePNG()
95   png_init_io(png_ptr, fp);  in PetscDrawImageSavePNG()
96 …png_set_IHDR(png_ptr, info_ptr, w, h, /*depth*/ 8, palette ? PNG_COLOR_TYPE_PALETTE : PNG_COLOR_TY…  in PetscDrawImageSavePNG()
97   if (palette) png_set_PLTE(png_ptr, info_ptr, (png_color *)palette, 256);  in PetscDrawImageSavePNG()
100   png_write_info(png_ptr, info_ptr);  in PetscDrawImageSavePNG()
101   for (row = 0; row < h; row++) png_write_row(png_ptr, pixels + row * stride);  in PetscDrawImageSavePNG()
102   png_write_end(png_ptr, NULL);  in PetscDrawImageSavePNG()
105   png_destroy_write_struct(&png_ptr, &info_ptr);  in PetscDrawImageSavePNG()