test-value.c

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/* test-value.c
 *
 * Creates all the types of tags supported in exif_entry_initialize() and
 * ensures that exif_entry_get_value() properly truncates the output of each
 * one according to the buffer size available.
 *
 * Copyright 2002 Lutz Mueller <lutz@users.sourceforge.net>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA  02110-1301  USA.
 *
 * SPDX-License-Identifier: LGPL-2.0-or-later
 */
 
#include <libexif/exif-utils.h>
#include <libexif/exif-data.h>
 
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
/*
 * List of tags to test, one per default initialized type.
 * There should be one for every block in exif_entry_initialize() and
 * exif_entry_get_value().
 */
static const ExifTag trunc_test_tags[] = {
        EXIF_TAG_PIXEL_X_DIMENSION,
        EXIF_TAG_SUBJECT_LOCATION,
        EXIF_TAG_IMAGE_WIDTH,
        EXIF_TAG_ORIENTATION,
        EXIF_TAG_SAMPLES_PER_PIXEL,
        EXIF_TAG_BITS_PER_SAMPLE,
        EXIF_TAG_X_RESOLUTION,
        EXIF_TAG_WHITE_POINT,
        EXIF_TAG_REFERENCE_BLACK_WHITE,
        EXIF_TAG_DATE_TIME,
        EXIF_TAG_IMAGE_DESCRIPTION,
        EXIF_TAG_EXIF_VERSION,
        EXIF_TAG_FLASH_PIX_VERSION,
        EXIF_TAG_COPYRIGHT,
        EXIF_TAG_FILE_SOURCE,
        EXIF_TAG_COMPONENTS_CONFIGURATION,
        EXIF_TAG_SCENE_TYPE,
        EXIF_TAG_YCBCR_SUB_SAMPLING,
        EXIF_TAG_PLANAR_CONFIGURATION,
};
 
/*
 * These tags produce different outputs depending on the amount of buffer space
 * available.
 */
static const ExifTag nonuniform_test_tags[] = {
        EXIF_TAG_RESOLUTION_UNIT,
        EXIF_TAG_COLOR_SPACE,
        EXIF_TAG_METERING_MODE,
};
 
/*
 * These tags need a nonzero rational number to be interesting.
 * They must have space for a rational or srational created automatically by
 * exif_entry_initialize().
 */
static const ExifTag rational_test_tags[] = {
        EXIF_TAG_FNUMBER,
        EXIF_TAG_APERTURE_VALUE,
        EXIF_TAG_MAX_APERTURE_VALUE,
        EXIF_TAG_FOCAL_LENGTH,
        EXIF_TAG_SUBJECT_DISTANCE,
        EXIF_TAG_EXPOSURE_TIME,
        EXIF_TAG_SHUTTER_SPEED_VALUE,
        EXIF_TAG_BRIGHTNESS_VALUE,
        EXIF_TAG_EXPOSURE_BIAS_VALUE,
};
 
/*
 * Verify that the entry is properly truncated to the buffer length within
 * exif_entry_get_value().  If uniform is zero, then only check that the
 * resulting string fits within the buffer and don't check its content.
 */
static void check_entry_trunc(ExifEntry *e, int uniform)
{
        unsigned int i;
        char v[1024], full[1024];  /* Large enough to never truncate output */
 
        printf ("Tag 0x%x\n", (int) e->tag);
 
        /* Get the full, untruncated string to use as the expected value */
        exif_entry_get_value (e, full, sizeof(full));
        printf ("Full: '%s'\n", full);
 
        for (i = strlen(full); i > 0; i--) {
                /* Make sure the buffer isn't NUL-terminated to begin with */
                memset(v, '*', sizeof(v));
                exif_entry_get_value (e, v, i);
                /* Truncate the full string by one on each iteration */
                full[i-1] = '\0';
                if ((strlen(v) >= i) || (uniform && strcmp(full, v))) {
                        printf("Bad truncation!\n");
                        printf("Length %2i: '%s'\n", i, v);
                        exit(1);
                }
        }
}
 
int
main (void)
{
        ExifData *data;
        ExifEntry *e;
        ExifMem *mem;
        unsigned i;
        static const ExifSRational r = {1., 20.};  /* a nonzero number */
        static const char user_comment[] = "ASCII\0\0\0A Long User Comment";
        static const char xp_comment[] = "U\0C\0S\0-\0002\0 \0C\0o\0m\0m\0e\0n\0t\0";
        static const char interop[] = "R98";
        static const char subsec[] = "130 ";
        static const ExifRational gpsh = {12., 1.};
        static const ExifRational gpsm = {34., 1.};
        static const ExifRational gpss = {56780., 1000.};
 
        data = exif_data_new ();
        if (!data) {
                fprintf (stderr, "Error running exif_data_new()\n");
                exit(13);
        }
 
        /* Full initialization/truncation tests */
        for (i=0; i < sizeof(trunc_test_tags)/sizeof(trunc_test_tags[0]); ++i) {
                e = exif_entry_new ();
                if (!e) {
                        fprintf (stderr, "Error running exif_entry_new()\n");
                        exit(13);
                }
                exif_content_add_entry (data->ifd[EXIF_IFD_0], e);
                exif_entry_initialize (e, trunc_test_tags[i]);
                check_entry_trunc(e, 1);
                exif_content_remove_entry (data->ifd[EXIF_IFD_0], e);
                exif_entry_unref (e);
        }
 
        /* Nonuniform initialization/truncation tests */
        for (i=0; i < sizeof(nonuniform_test_tags)/sizeof(nonuniform_test_tags[0]);
                 ++i) {
                e = exif_entry_new ();
                if (!e) {
                        fprintf (stderr, "Error running exif_entry_new()\n");
                        exit(13);
                }
                exif_content_add_entry (data->ifd[EXIF_IFD_0], e);
                exif_entry_initialize (e, nonuniform_test_tags[i]);
                check_entry_trunc(e, 0);
                exif_content_remove_entry (data->ifd[EXIF_IFD_0], e);
                exif_entry_unref (e);
        }
 
        /* Rational number initialization/truncation tests */
        for (i=0; i < sizeof(rational_test_tags)/sizeof(rational_test_tags[0]);
                 ++i) {
                e = exif_entry_new ();
                if (!e) {
                        fprintf (stderr, "Error running exif_entry_new()\n");
                        exit(13);
                }
                exif_content_add_entry (data->ifd[EXIF_IFD_0], e);
                exif_entry_initialize (e, rational_test_tags[i]);
                exif_set_srational (e->data, exif_data_get_byte_order (data), r);
                /* In case this tag needs an unsigned rational instead,
                 * fix the type automatically */
                exif_entry_fix (e);
                check_entry_trunc(e, 1);
                exif_content_remove_entry (data->ifd[EXIF_IFD_0], e);
                exif_entry_unref (e);
        }
 
        /* Create a memory allocator to manage the remaining ExifEntry structs */
        mem = exif_mem_new_default();
        if (!mem) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
 
        /* EXIF_TAG_SUB_SEC_TIME initialization/truncation tests */
        e = exif_entry_new_mem (mem);
        if (!e) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_content_add_entry (data->ifd[EXIF_IFD_0], e);
        exif_entry_initialize (e, EXIF_TAG_SUB_SEC_TIME);
        e->size = sizeof(subsec);  /* include NUL */
        e->components = e->size;
        /* Allocate memory to use for holding the tag data */
        e->data = exif_mem_alloc(mem, e->size);
        if (!e->data) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        memcpy(e->data, subsec, e->size);
        check_entry_trunc(e, 1);
        exif_content_remove_entry (data->ifd[EXIF_IFD_0], e);
        exif_entry_unref (e);
 
        /* EXIF_TAG_USER_COMMENT initialization/truncation tests */
        e = exif_entry_new_mem (mem);
        if (!e) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_content_add_entry (data->ifd[EXIF_IFD_0], e);
        exif_entry_initialize (e, EXIF_TAG_USER_COMMENT);
        e->size = sizeof(user_comment) - 1;
        e->components = e->size;
        /* Allocate memory to use for holding the tag data */
        e->data = exif_mem_alloc(mem, e->size);
        if (!e->data) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        memcpy(e->data, user_comment, e->size);
        check_entry_trunc(e, 1);
        exif_content_remove_entry (data->ifd[EXIF_IFD_0], e);
        exif_entry_unref (e);
 
        /* EXIF_TAG_XP_COMMENT truncation tests */
        e = exif_entry_new_mem (mem);
        if (!e) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_content_add_entry (data->ifd[EXIF_IFD_0], e);
        exif_entry_initialize (e, EXIF_TAG_XP_COMMENT);
        e->format = EXIF_FORMAT_BYTE;
        e->size = sizeof(xp_comment) - 1;
        e->components = e->size;
        /* Allocate memory to use for holding the tag data */
        e->data = exif_mem_alloc(mem, e->size);
        if (!e->data) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        memcpy(e->data, xp_comment, e->size);
        check_entry_trunc(e, 1);
        exif_content_remove_entry (data->ifd[EXIF_IFD_0], e);
        exif_entry_unref (e);
 
        /* EXIF_TAG_INTEROPERABILITY_VERSION truncation tests */
        e = exif_entry_new_mem (mem);
        if (!e) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_content_add_entry (data->ifd[EXIF_IFD_INTEROPERABILITY], e);
        exif_entry_initialize (e, EXIF_TAG_INTEROPERABILITY_VERSION);
        e->format = EXIF_FORMAT_UNDEFINED;  /* The spec says ASCII, but libexif
                                               allows UNDEFINED */
        e->size = sizeof(interop);  /* include NUL */
        e->components = e->size;
        /* Allocate memory to use for holding the tag data */
        e->data = exif_mem_alloc(mem, e->size);
        if (!e->data) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        memcpy(e->data, interop, e->size);
        check_entry_trunc(e, 1);
        exif_content_remove_entry (data->ifd[EXIF_IFD_INTEROPERABILITY], e);
        exif_entry_unref (e);
 
        /* EXIF_TAG_GPS_VERSION_ID truncation tests */
        e = exif_entry_new_mem (mem);
        if (!e) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_content_add_entry (data->ifd[EXIF_IFD_GPS], e);
        exif_entry_initialize (e, EXIF_TAG_GPS_VERSION_ID);
        assert(e->format == EXIF_FORMAT_BYTE);
        assert(e->size == 4);
        assert(e->components == e->size);
        e->data[0] = 2;
        e->data[1] = 2;
        e->data[2] = 0;
        e->data[3] = 0;
        check_entry_trunc(e, 1);
        exif_content_remove_entry (data->ifd[EXIF_IFD_GPS], e);
        exif_entry_unref (e);
 
        /* EXIF_TAG_GPS_ALTITUDE_REF truncation tests */
        e = exif_entry_new_mem (mem);
        if (!e) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_content_add_entry (data->ifd[EXIF_IFD_GPS], e);
        exif_entry_initialize (e, EXIF_TAG_GPS_ALTITUDE_REF);
        assert(e->format == EXIF_FORMAT_BYTE);
        assert(e->size == 1);
        assert(e->components == e->size);
        e->data[0] = 1;
        check_entry_trunc(e, 1);
        exif_content_remove_entry (data->ifd[EXIF_IFD_GPS], e);
        exif_entry_unref (e);
 
        /* EXIF_TAG_GPS_TIME_STAMP truncation tests */
        e = exif_entry_new_mem (mem);
        if (!e) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_content_add_entry (data->ifd[EXIF_IFD_GPS], e);
        exif_entry_initialize (e, EXIF_TAG_GPS_TIME_STAMP);
        assert(e->format == EXIF_FORMAT_RATIONAL);
        assert(e->components == 3);
        assert(e->size == e->components * exif_format_get_size(EXIF_FORMAT_RATIONAL));
        exif_set_rational(e->data, exif_data_get_byte_order (data), gpsh);
        exif_set_rational(e->data+8, exif_data_get_byte_order (data), gpsm);
        exif_set_rational(e->data+16, exif_data_get_byte_order (data), gpss);
        check_entry_trunc(e, 1);
        exif_content_remove_entry (data->ifd[EXIF_IFD_GPS], e);
        exif_entry_unref (e);
 
        /* EXIF_TAG_SUBJECT_AREA truncation tests */
        e = exif_entry_new_mem (mem);
        if (!e) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_content_add_entry (data->ifd[EXIF_IFD_0], e);
        exif_entry_initialize (e, EXIF_TAG_SUBJECT_AREA);
        e->format = EXIF_FORMAT_SHORT;
        /* This tag is interpreted differently depending on # components */
        /* Rectangle */
        e->components = 4;
        e->size = e->components * exif_format_get_size(EXIF_FORMAT_SHORT);
        /* Allocate memory to use for holding the tag data */
        e->data = exif_mem_alloc(mem, e->size);
        if (!e->data) {
                fprintf (stderr, "Out of memory\n");
                exit(13);
        }
        exif_set_short(e->data, exif_data_get_byte_order (data), 123);
        exif_set_short(e->data+2, exif_data_get_byte_order (data), 456);
        exif_set_short(e->data+4, exif_data_get_byte_order (data), 78);
        exif_set_short(e->data+6, exif_data_get_byte_order (data), 90);
        check_entry_trunc(e, 1);
        /* Circle */
        e->components = 3;
        e->size = e->components * exif_format_get_size(EXIF_FORMAT_SHORT);
        check_entry_trunc(e, 1);
        /* Centre */
        e->components = 2;
        e->size = e->components * exif_format_get_size(EXIF_FORMAT_SHORT);
        check_entry_trunc(e, 1);
        /* Invalid */
        e->components = 1;
        e->size = e->components * exif_format_get_size(EXIF_FORMAT_SHORT);
        check_entry_trunc(e, 1);
        exif_content_remove_entry (data->ifd[EXIF_IFD_0], e);
        exif_entry_unref (e);
 
        exif_mem_unref(mem);
        exif_data_unref (data);
 
        return 0;
}