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/* See LICENSE file for copyright and license details. */
#include "common.h"
#ifndef TEST
int
libsimple_get_stack_space(uintptr_t *restrict low, uintptr_t *restrict high)
{
char buf[4096], *line;
int fd;
ssize_t r;
size_t off = 0;
size_t lineoff, linelen;
fd = open("/proc/self/maps", O_RDONLY);
if (fd < 0)
return -1;
for (;;) {
read_again:
r = read(fd, &buf[off], sizeof(buf) - off);
if (r <= 0) {
if (r && errno == EINTR)
continue;
close(fd);
if (!r)
errno = EIO;
return -1;
}
off += (size_t)r;
for (lineoff = 0; lineoff < off; lineoff += linelen) {
char *lf = strchr(&buf[lineoff], '\n');
if (!lf) {
memmove(&buf[0], &buf[lineoff], off -= lineoff);
goto read_again;
}
line = &buf[lineoff];
linelen = (size_t)(&lf[1] - line);
if (linelen > sizeof(" [stack]\n") - 1U)
if (!strcmp(&line[linelen - (sizeof(" [stack]\n") - 1U)], " [stack]\n"))
goto line_found;
}
}
line_found:
close(fd);
*low = (uintptr_t)strtoumax(line, &line, 16);
*high = (uintptr_t)strtoumax(&line[1], &line, 16);
if (*low > *high) {
*low ^= *high;
*high ^= *low;
*low ^= *high;
}
return 0;
}
#else
#include "test.h"
int
main(void)
{
return 0;
}
#endif
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