Files
obsw/bsp_z7/newlib/write.c
T
2025-10-24 17:46:01 +02:00

50 lines
1.1 KiB
C

#include "xil_printf.h"
#include "xparameters.h"
#include "../hardware/interface_access.h"
#include "../hardware/interface_fds.h"
#include <errno.h>
#include <reent.h>
#include <unistd.h>
int write(int fd, const void *ptr, size_t len) {
if (ptr == NULL) {
_REENT_ERRNO(_REENT) = EINVAL;
return -1;
}
//TODO check len
// 0 is stdin, do not write to it
if (fd < 1) {
_REENT_ERRNO(_REENT) = EBADF;
return -1;
}
// we only support a single debug UART, so
// stdout and stderr are the same and go to the xilinx stdout UART
// We output directely to avoid loops and allow debugging (not via a write)
if (fd < 3) {
size_t todo;
const char *data = ptr;
for (todo = 0; todo < len; todo++) {
outbyte(*data++);
}
return len;
}
if (fd < INTERFACE_FDS_NEXT) {
int result = hw_interface_write(fd, ptr, len);
if (result >= 0) {
return result;
} else if (_REENT_ERRNO(_REENT) != EBADF) {
return result;
}
// continue if fd did not match to try other fd providers
}
// we do not have dynamic fds, so fd is invalid
_REENT_ERRNO(_REENT) = EBADF;
return -1;
}