diff options
Diffstat (limited to 'lib/libppm1.c')
| -rw-r--r-- | lib/libppm1.c | 193 |
1 files changed, 130 insertions, 63 deletions
diff --git a/lib/libppm1.c b/lib/libppm1.c index 97110730..c1eb152c 100644 --- a/lib/libppm1.c +++ b/lib/libppm1.c @@ -20,6 +20,8 @@ #include <stdio.h> #include <errno.h> +#include "netpbm/mallocvar.h" +#include "netpbm/nstring.h" #include "ppm.h" #include "libppm.h" #include "pgm.h" @@ -29,8 +31,6 @@ #include "pam.h" #include "libpam.h" #include "fileio.h" -#include "mallocvar.h" -#include "nstring.h" pixel * @@ -49,12 +49,11 @@ ppm_allocrow(unsigned int const cols) { void -ppm_init( argcP, argv ) - int* argcP; - char* argv[]; - { +ppm_init(int * const argcP, char ** const argv) { pgm_init( argcP, argv ); - } +} + + void ppm_nextimage(FILE * const fileP, @@ -79,7 +78,7 @@ ppm_readppminitrest(FILE * const fileP, maxval = pm_getuint(fileP); if (maxval > PPM_OVERALLMAXVAL) pm_error("maxval of input image (%u) is too large. " - "The maximum allowed by the PPM is %u.", + "The maximum allowed by the PPM format is %u.", maxval, PPM_OVERALLMAXVAL); if (maxval == 0) pm_error("maxval of input image is zero."); @@ -100,10 +99,13 @@ 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); @@ -184,6 +186,92 @@ readPpmRow(FILE * const fileP, static void +interpRasterRowRaw(const unsigned char * const rowBuffer, + pixel * const pixelrow, + unsigned int const cols, + unsigned int const bytesPerSample) { + + unsigned int bufferCursor; + + bufferCursor = 0; /* start at beginning of rowBuffer[] */ + + if (bytesPerSample == 1) { + unsigned int col; + for (col = 0; col < cols; ++col) { + pixval const r = rowBuffer[bufferCursor++]; + pixval const g = rowBuffer[bufferCursor++]; + pixval const b = rowBuffer[bufferCursor++]; + PPM_ASSIGN(pixelrow[col], r, g, b); + } + } else { + /* two byte samples */ + unsigned int col; + for (col = 0; col < cols; ++col) { + pixval r, g, b; + + r = rowBuffer[bufferCursor++] << 8; + r |= rowBuffer[bufferCursor++]; + + g = rowBuffer[bufferCursor++] << 8; + g |= rowBuffer[bufferCursor++]; + + b = rowBuffer[bufferCursor++] << 8; + b |= rowBuffer[bufferCursor++]; + + PPM_ASSIGN(pixelrow[col], r, g, b); + } + } +} + + + +static void +validateRppmRow(pixel * const pixelrow, + unsigned int const cols, + pixval const maxval, + const char ** const errorP) { +/*---------------------------------------------------------------------------- + Check for sample values above maxval in input. + + Note: a program that wants to deal with invalid sample values itself can + simply make sure it uses a sufficiently high maxval on the read function + call, so this validation never fails. +-----------------------------------------------------------------------------*/ + if (maxval == 255 || maxval == 65535) { + /* There's no way a sample can be invalid, so we don't need to look at + the samples individually. + */ + *errorP = NULL; + } else { + unsigned int col; + + for (col = 0, *errorP = NULL; col < cols && !*errorP; ++col) { + pixval const r = PPM_GETR(pixelrow[col]); + pixval const g = PPM_GETG(pixelrow[col]); + pixval const b = PPM_GETB(pixelrow[col]); + + if (r > maxval) + pm_asprintf( + errorP, + "Red sample value %u is greater than maxval (%u)", + r, maxval); + else if (g > maxval) + pm_asprintf( + errorP, + "Green sample value %u is greater than maxval (%u)", + g, maxval); + else if (b > maxval) + pm_asprintf( + errorP, + "Blue sample value %u is greater than maxval (%u)", + b, maxval); + } + } +} + + + +static void readRppmRow(FILE * const fileP, pixel * const pixelrow, unsigned int const cols, @@ -199,60 +287,35 @@ readRppmRow(FILE * const fileP, MALLOCARRAY(rowBuffer, bytesPerRow); if (rowBuffer == NULL) - asprintfN(&error, "Unable to allocate memory for row buffer " - "for %u columns", cols); + pm_asprintf(&error, "Unable to allocate memory for row buffer " + "for %u columns", cols); else { ssize_t rc; rc = fread(rowBuffer, 1, bytesPerRow, fileP); if (feof(fileP)) - asprintfN(&error, "Unexpected EOF reading row of PPM image."); + pm_asprintf(&error, "Unexpected EOF reading row of PPM image."); else if (ferror(fileP)) - asprintfN(&error, "Error reading row. fread() errno=%d (%s)", - errno, strerror(errno)); - else if (rc != bytesPerRow) - asprintfN(&error, "Error reading row. Short read of %u bytes " - "instead of %u", rc, bytesPerRow); + pm_asprintf(&error, "Error reading row. fread() errno=%d (%s)", + errno, strerror(errno)); else { - unsigned int bufferCursor; - - error = NULL; - - bufferCursor = 0; /* start at beginning of rowBuffer[] */ - - if (bytesPerSample == 1) { - unsigned int col; - for (col = 0; col < cols; ++col) { - pixval const r = rowBuffer[bufferCursor++]; - pixval const g = rowBuffer[bufferCursor++]; - pixval const b = rowBuffer[bufferCursor++]; - PPM_ASSIGN(pixelrow[col], r, g, b); - } - } else { - /* two byte samples */ - unsigned int col; - for (col = 0; col < cols; ++col) { - pixval r, g, b; - - r = rowBuffer[bufferCursor++] << 8; - r |= rowBuffer[bufferCursor++]; - - g = rowBuffer[bufferCursor++] << 8; - g |= rowBuffer[bufferCursor++]; - - b = rowBuffer[bufferCursor++] << 8; - b |= rowBuffer[bufferCursor++]; - - PPM_ASSIGN(pixelrow[col], r, g, b); - } + size_t const bytesRead = rc; + if (bytesRead != bytesPerRow) + pm_asprintf(&error, + "Error reading row. Short read of %u bytes " + "instead of %u", (unsigned)bytesRead, bytesPerRow); + else { + interpRasterRowRaw(rowBuffer, pixelrow, cols, bytesPerSample); + + validateRppmRow(pixelrow, cols, maxval, &error); } } free(rowBuffer); } if (error) { pm_errormsg("%s", error); - strfree(error); + pm_strfree(error); pm_longjmp(); } } @@ -305,10 +368,10 @@ 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 { @@ -316,10 +379,12 @@ readPbmRow(FILE * const fileP, pm_setjmpbufsave(&jmpbuf, &origJmpbufP); - pbm_readpbmrow(fileP, bitrow, cols, format); + pbm_readpbmrow_packed(fileP, bitrow, cols, format); for (col = 0; col < cols; ++col) { - pixval const g = (bitrow[col] == PBM_WHITE) ? maxval : 0; + pixval const g = + ((bitrow[col/8] >> (7 - col%8)) & 0x1) == PBM_WHITE ? + maxval : 0; PPM_ASSIGN(pixelrow[col], g, g, g); } pm_setjmpbuf(origJmpbufP); @@ -408,30 +473,32 @@ ppm_readppm(FILE * const fileP, void ppm_check(FILE * const fileP, - enum pm_check_type const check_type, + enum pm_check_type const checkType, int const format, int const cols, int const rows, pixval const maxval, - enum pm_check_code * const retval_p) { + enum pm_check_code * const retvalP) { if (rows < 0) pm_error("Invalid number of rows passed to ppm_check(): %d", rows); if (cols < 0) pm_error("Invalid number of columns passed to ppm_check(): %d", cols); - if (check_type != PM_CHECK_BASIC) { - if (retval_p) *retval_p = PM_CHECK_UNKNOWN_TYPE; + if (checkType != PM_CHECK_BASIC) { + if (retvalP) + *retvalP = PM_CHECK_UNKNOWN_TYPE; } else if (PPM_FORMAT_TYPE(format) == PBM_TYPE) { - pbm_check(fileP, check_type, format, cols, rows, retval_p); + pbm_check(fileP, checkType, format, cols, rows, retvalP); } else if (PPM_FORMAT_TYPE(format) == PGM_TYPE) { - pgm_check(fileP, check_type, format, cols, rows, maxval, retval_p); + pgm_check(fileP, checkType, format, cols, rows, maxval, retvalP); } else if (format != RPPM_FORMAT) { - if (retval_p) *retval_p = PM_CHECK_UNCHECKABLE; + if (retvalP) + *retvalP = PM_CHECK_UNCHECKABLE; } else { - pm_filepos const bytes_per_row = cols * 3 * (maxval > 255 ? 2 : 1); - pm_filepos const need_raster_size = rows * bytes_per_row; + pm_filepos const bytesPerRow = cols * 3 * (maxval > 255 ? 2 : 1); + pm_filepos const needRasterSize = rows * bytesPerRow; - pm_check(fileP, check_type, need_raster_size, retval_p); + pm_check(fileP, checkType, needRasterSize, retvalP); } } |