blob: 22ee29f711905627bea6798f9b2f5a0a691ab967 [file] [log] [blame]
/* exif-utils.c
*
* Copyright (c) 2001 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.
*/
#include <config.h>
#include <libexif/exif-utils.h>
void
exif_array_set_byte_order (ExifFormat f, unsigned char *b, unsigned int n,
ExifByteOrder o_orig, ExifByteOrder o_new)
{
unsigned int j;
unsigned int fs = exif_format_get_size (f);
ExifShort s;
ExifSShort ss;
ExifLong l;
ExifSLong sl;
ExifRational r;
ExifSRational sr;
if (!b || !n || !fs) return;
switch (f) {
case EXIF_FORMAT_SHORT:
for (j = 0; j < n; j++) {
s = exif_get_short (b + j * fs, o_orig);
exif_set_short (b + j * fs, o_new, s);
}
break;
case EXIF_FORMAT_SSHORT:
for (j = 0; j < n; j++) {
ss = exif_get_sshort (b + j * fs, o_orig);
exif_set_sshort (b + j * fs, o_new, ss);
}
break;
case EXIF_FORMAT_LONG:
for (j = 0; j < n; j++) {
l = exif_get_long (b + j * fs, o_orig);
exif_set_long (b + j * fs, o_new, l);
}
break;
case EXIF_FORMAT_RATIONAL:
for (j = 0; j < n; j++) {
r = exif_get_rational (b + j * fs, o_orig);
exif_set_rational (b + j * fs, o_new, r);
}
break;
case EXIF_FORMAT_SLONG:
for (j = 0; j < n; j++) {
sl = exif_get_slong (b + j * fs, o_orig);
exif_set_slong (b + j * fs, o_new, sl);
}
break;
case EXIF_FORMAT_SRATIONAL:
for (j = 0; j < n; j++) {
sr = exif_get_srational (b + j * fs, o_orig);
exif_set_srational (b + j * fs, o_new, sr);
}
break;
case EXIF_FORMAT_UNDEFINED:
case EXIF_FORMAT_BYTE:
case EXIF_FORMAT_ASCII:
default:
/* Nothing here. */
break;
}
}
ExifSShort
exif_get_sshort (const unsigned char *buf, ExifByteOrder order)
{
if (!buf) return 0;
switch (order) {
case EXIF_BYTE_ORDER_MOTOROLA:
return ((buf[0] << 8) | buf[1]);
case EXIF_BYTE_ORDER_INTEL:
return ((buf[1] << 8) | buf[0]);
}
/* Won't be reached */
return (0);
}
ExifShort
exif_get_short (const unsigned char *buf, ExifByteOrder order)
{
return (exif_get_sshort (buf, order) & 0xffff);
}
void
exif_set_sshort (unsigned char *b, ExifByteOrder order, ExifSShort value)
{
if (!b) return;
switch (order) {
case EXIF_BYTE_ORDER_MOTOROLA:
b[0] = (unsigned char) (value >> 8);
b[1] = (unsigned char) value;
break;
case EXIF_BYTE_ORDER_INTEL:
b[0] = (unsigned char) value;
b[1] = (unsigned char) (value >> 8);
break;
}
}
void
exif_set_short (unsigned char *b, ExifByteOrder order, ExifShort value)
{
exif_set_sshort (b, order, value);
}
ExifSLong
exif_get_slong (const unsigned char *b, ExifByteOrder order)
{
if (!b) return 0;
switch (order) {
case EXIF_BYTE_ORDER_MOTOROLA:
return ((b[0] << 24) | (b[1] << 16) | (b[2] << 8) | b[3]);
case EXIF_BYTE_ORDER_INTEL:
return ((b[3] << 24) | (b[2] << 16) | (b[1] << 8) | b[0]);
}
/* Won't be reached */
return (0);
}
void
exif_set_slong (unsigned char *b, ExifByteOrder order, ExifSLong value)
{
if (!b) return;
switch (order) {
case EXIF_BYTE_ORDER_MOTOROLA:
b[0] = (unsigned char) (value >> 24);
b[1] = (unsigned char) (value >> 16);
b[2] = (unsigned char) (value >> 8);
b[3] = (unsigned char) value;
break;
case EXIF_BYTE_ORDER_INTEL:
b[3] = (unsigned char) (value >> 24);
b[2] = (unsigned char) (value >> 16);
b[1] = (unsigned char) (value >> 8);
b[0] = (unsigned char) value;
break;
}
}
ExifLong
exif_get_long (const unsigned char *buf, ExifByteOrder order)
{
return (exif_get_slong (buf, order) & 0xffffffff);
}
void
exif_set_long (unsigned char *b, ExifByteOrder order, ExifLong value)
{
exif_set_slong (b, order, value);
}
ExifSRational
exif_get_srational (const unsigned char *buf, ExifByteOrder order)
{
ExifSRational r;
r.numerator = buf ? exif_get_slong (buf, order) : 0;
r.denominator = buf ? exif_get_slong (buf + 4, order) : 0;
return (r);
}
ExifRational
exif_get_rational (const unsigned char *buf, ExifByteOrder order)
{
ExifRational r;
r.numerator = buf ? exif_get_long (buf, order) : 0;
r.denominator = buf ? exif_get_long (buf + 4, order) : 0;
return (r);
}
void
exif_set_rational (unsigned char *buf, ExifByteOrder order,
ExifRational value)
{
if (!buf) return;
exif_set_long (buf, order, value.numerator);
exif_set_long (buf + 4, order, value.denominator);
}
void
exif_set_srational (unsigned char *buf, ExifByteOrder order,
ExifSRational value)
{
if (!buf) return;
exif_set_slong (buf, order, value.numerator);
exif_set_slong (buf + 4, order, value.denominator);
}
/*! This function converts rather UCS-2LE than UTF-16 to UTF-8.
* It should really be replaced by iconv().
*/
void
exif_convert_utf16_to_utf8 (char *out, const unsigned short *in, int maxlen)
{
if (maxlen <= 0) {
return;
}
while (*in) {
if (*in < 0x80) {
if (maxlen > 1) {
*out++ = (char)*in++;
maxlen--;
} else {
break;
}
} else if (*in < 0x800) {
if (maxlen > 2) {
*out++ = ((*in >> 6) & 0x1F) | 0xC0;
*out++ = (*in++ & 0x3F) | 0x80;
maxlen -= 2;
} else {
break;
}
} else {
if (maxlen > 2) {
*out++ = ((*in >> 12) & 0x0F) | 0xE0;
*out++ = ((*in >> 6) & 0x3F) | 0x80;
*out++ = (*in++ & 0x3F) | 0x80;
maxlen -= 3;
} else {
break;
}
}
}
*out = 0;
}