added flashrw

flashrw/syscall.c

@@ -0,0 +1,161 @@
+/*
+ * 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;
+}
+
+#if 0
+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;
+}
+#endif
+
+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;
+}