Files
stm32uav/syscall.c
2022-09-27 20:01:14 +02:00

160 lines
2.4 KiB
C

/*
* Copyright 2022 Oleg Borodin <borodin@unix7.org>
*/
#include <libopencm3/stm32/usart.h>
#include <stdlib.h>
#include <reent.h>
#include <sys/stat.h>
#include <sys/errno.h>
#include <errno.h>
#include <usartu.h>
#undef errno
extern int errno;
char *__env[1] = { 0 };
char **environ = __env;
int _execve(char *name, char **argv, char **env) {
errno = ENOMEM;
return -1;
}
int _fork(void) {
errno = EAGAIN;
return -1;
}
int _getpid(void) {
return 1;
}
int _kill(int pid, int sig) {
errno = EINVAL;
return -1;
}
void _exit(int i) {
while (1);
}
int _isatty(int file) {
return 1;
}
int _fstat(int file, struct stat *st) {
st->st_mode = S_IFCHR;
return 0;
}
int _link(char *old, char *new) {
errno = EMLINK;
return -1;
}
int _lseek(int file, int ptr, int dir) {
return 0;
}
int _open(const char *name, int flags, int mode) {
return -1;
}
#define STDIN 0
#define STDOUT 1
#define STDERR 3
int _read(int file, char *ptr, int len) {
int i = 0;
while (i < len) {
ptr[i++] = 0;
}
return i;
}
int _write(int file, char *ptr, int len) {
int i;
if ((file == STDOUT) || (file == STDERR)) {
for (i = 0; i < len; i++) {
usart_putc(USART1, ptr[i]);
}
return len;
}
return 0;
}
int _stat(char *file, struct stat *st) {
st->st_mode = S_IFCHR;
return 0;
}
int _close(int file) {
return -1;
}
int _times(struct tms *buf) {
return -1;
}
int _unlink(char *name) {
errno = ENOENT;
return -1;
}
int _wait(int *status) {
errno = ECHILD;
return -1;
}
void *xxx_sbrk(int incr) {
extern unsigned char *_end;
static unsigned char *heap = NULL;
unsigned char *prev_heap;
if (heap == NULL) {
heap = (unsigned char*)&_end;
}
prev_heap = heap;
heap += incr;
return prev_heap;
}
register char* stack_ptr __asm__ ("sp");
caddr_t __attribute__((weak)) _sbrk (int incr) {
extern char end __asm__ ("_end");
static char * heap_end;
char * prev_heap_end;
if (heap_end == NULL) {
heap_end = &end;
}
prev_heap_end = heap_end;
if (heap_end + incr > stack_ptr) {
#if 0
extern void abort (void);
_write (1, "_sbrk: Heap and stack collision\n", 32);
abort ();
#else
errno = ENOMEM;
return (caddr_t) -1;
#endif
}
heap_end += incr;
return (caddr_t) prev_heap_end;
}