Initial commit

Src/syscalls.c

@@ -0,0 +1,170 @@
+/* Support files for GNU libc.  Files in the system namespace go here.
+   Files in the C namespace (ie those that do not start with an
+   underscore) go in .c.  */
+
+#include <_ansi.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/fcntl.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+#include <sys/time.h>
+#include <sys/times.h>
+#include <errno.h>
+#include <reent.h>
+#include <unistd.h>
+#include <sys/wait.h>
+#include "gd32e23x_usart.h"
+
+#undef errno
+extern int errno;
+
+extern int __io_putchar(int ch) __attribute__((weak));
+extern int __io_getchar(void) __attribute__((weak));
+
+caddr_t _sbrk(int incr)
+{
+  extern char _end[];
+  static char *curbrk = _end;
+
+  if ((curbrk + incr < _end))
+    return NULL - 1;
+
+  curbrk += incr;
+  return curbrk - incr;
+}
+
+/*
+ * _gettimeofday primitive (Stub function)
+ * */
+int _gettimeofday (struct timeval * tp, struct timezone * tzp)
+{
+  /* Return fixed data for the timezone.  */
+  if (tzp)
+    {
+      tzp->tz_minuteswest = 0;
+      tzp->tz_dsttime = 0;
+    }
+
+  return 0;
+}
+void initialise_monitor_handles()
+{
+}
+
+int _getpid(void)
+{
+	return 1;
+}
+
+int _kill(int pid, int sig)
+{
+	errno = EINVAL;
+	return -1;
+}
+
+void _exit (int status)
+{
+	_kill(status, -1);
+	while (1) {}
+}
+
+int _write(int file, char *ptr, int len)
+{
+	int DataIdx;
+
+		for (DataIdx = 0; DataIdx < len; DataIdx++)
+		{
+		   __io_putchar( *ptr++ );
+		}
+	return len;
+}
+
+int _close(int file)
+{
+	return -1;
+}
+
+int _fstat(int file, struct stat *st)
+{
+	st->st_mode = S_IFCHR;
+	return 0;
+}
+
+int _isatty(int file)
+{
+	return 1;
+}
+
+int _lseek(int file, int ptr, int dir)
+{
+	return 0;
+}
+
+int _read(int file, char *ptr, int len)
+{
+	int DataIdx;
+
+	for (DataIdx = 0; DataIdx < len; DataIdx++)
+	{
+	  *ptr++ = __io_getchar();
+	}
+
+   return len;
+}
+
+int _open(char *path, int flags, ...)
+{
+	/* Pretend like we always fail */
+	return -1;
+}
+
+int _wait(int *status)
+{
+	errno = ECHILD;
+	return -1;
+}
+
+int _unlink(char *name)
+{
+	errno = ENOENT;
+	return -1;
+}
+
+int _times(struct tms *buf)
+{
+	return -1;
+}
+
+int _stat(char *file, struct stat *st)
+{
+	st->st_mode = S_IFCHR;
+	return 0;
+}
+
+int _link(char *old, char *new)
+{
+	errno = EMLINK;
+	return -1;
+}
+
+int _fork(void)
+{
+	errno = EAGAIN;
+	return -1;
+}
+
+int _execve(char *name, char **argv, char **env)
+{
+	errno = ENOMEM;
+	return -1;
+}
+
+// USART0 printf重定向实现
+int __io_putchar(int ch) {
+    // 等待发送缓冲区空
+    while (usart_flag_get(USART0, USART_FLAG_TBE) == RESET) {}
+    usart_data_transmit(USART0, (uint8_t)ch);
+    return ch;
+}