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/* See LICENSE file for copyright and license details. */
#include "stream.h"
#include "util.h"
#include <fcntl.h>
#include <math.h>
#include <stdint.h>
#include <string.h>
#include <unistd.h>
USAGE("[-axyz] operation right-hand-stream")
static int skip_a = 0;
static int skip_x = 0;
static int skip_y = 0;
static int skip_z = 0;
/* Because the syntax for a function returning a function pointer is disgusting. */
typedef void (*process_func)(struct stream *left, struct stream *right, size_t n);
#define LIST_OPERATORS\
X(add, *lh += rh)\
X(sub, *lh -= rh)\
X(mul, *lh *= rh)\
X(div, *lh /= rh)\
X(exp, *lh = pow(*lh, rh))\
X(log, *lh = log(*lh) / log(rh))\
X(min, *lh = *lh < rh ? *lh : rh)\
X(max, *lh = *lh > rh ? *lh : rh)\
X(abs, *lh = fabs(*lh - rh) + rh)
#define X(NAME, ALGO)\
static void\
process_lf_##NAME(struct stream *left, struct stream *right, size_t n)\
{\
size_t i;\
double *lh, rh;\
for (i = 0; i < n; i += 4 * sizeof(double)) {\
if (!skip_x) {\
lh = ((double *)(left->buf + i)) + 0, rh = ((double *)(right->buf + i))[0];\
ALGO;\
}\
if (!skip_y) {\
lh = ((double *)(left->buf + i)) + 1, rh = ((double *)(right->buf + i))[1];\
ALGO;\
}\
if (!skip_z) {\
lh = ((double *)(left->buf + i)) + 2, rh = ((double *)(right->buf + i))[2];\
ALGO;\
}\
if (!skip_a) {\
lh = ((double *)(left->buf + i)) + 3, rh = ((double *)(right->buf + i))[3];\
ALGO;\
}\
}\
}
LIST_OPERATORS
#undef X
static process_func
get_lf_process(const char *operation)
{
#define X(NAME, ALGO)\
if (!strcmp(operation, #NAME)) return process_lf_##NAME;
LIST_OPERATORS
#undef X
eprintf("algorithm not recognised: %s\n", operation);
return NULL;
}
int
main(int argc, char *argv[])
{
struct stream left, right;
process_func process = NULL;
ARGBEGIN {
case 'a':
skip_a = 1;
break;
case 'x':
skip_x = 1;
break;
case 'y':
skip_y = 1;
break;
case 'z':
skip_z = 1;
break;
default:
usage();
} ARGEND;
if (argc != 2)
usage();
left.file = "<stdin>";
left.fd = STDIN_FILENO;
einit_stream(&left);
right.file = argv[1];
right.fd = eopen(right.file, O_RDONLY);
einit_stream(&right);
if (!strcmp(left.pixfmt, "xyza"))
process = get_lf_process(argv[0]);
else
eprintf("pixel format %s is not supported, try xyza\n", left.pixfmt);
fprint_stream_head(stdout, &left);
efflush(stdout, "<stdout>");
process_two_streams(&left, &right, STDOUT_FILENO, "<stdout>", process);
return 0;
}
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