1 files changed, 157 insertions, 0 deletions
diff --git a/libmaple/syscalls.c b/libmaple/syscalls.c
new file mode 100644
index 0000000..390cecd
--- /dev/null
+++ b/libmaple/syscalls.c
@@ -0,0 +1,157 @@
+#include "libmaple.h"
+#include <sys/stat.h>
+
+/* _end is set in the linker command file */
+extern caddr_t _end;
+
+/* just in case, most boards have at least some memory */
+#ifndef RAMSIZE
+#  define RAMSIZE             (caddr_t)0x50000
+#endif
+
+#define STACK_TOP 0x20000800
+
+void uart_send(const char*str);
+
+/*
+ * sbrk -- changes heap size size. Get nbytes more
+ *         RAM. We just increment a pointer in what's
+ *         left of memory on the board.
+ */
+caddr_t
+_sbrk(nbytes)
+int nbytes;
+{
+    static caddr_t heap_ptr = NULL;
+    caddr_t        base;
+
+    if (heap_ptr == NULL) {
+        heap_ptr = (caddr_t)&_end;
+    }
+
+    if ((STACK_TOP - (unsigned int)heap_ptr) >= 0) {
+        base = heap_ptr;
+        heap_ptr += nbytes;
+        return (base);
+    } else {
+        uart_send("heap full!\r\n");
+        return ((caddr_t)-1);
+    }
+}
+
+int _open(const char *path, int flags, ...)
+{
+    return 1;
+}
+
+int _close(int fd)
+{
+    return 0;
+}
+
+int _fstat(int fd, struct stat *st)
+{
+    st->st_mode = S_IFCHR;
+    return 0;
+}
+
+int _isatty(int fd)
+{
+    return 1;
+}
+
+int isatty(int fd)
+{
+    return 1;
+}
+
+int _lseek(int fd, off_t pos, int whence)
+{
+    return -1;
+}
+
+unsigned char getch(void)
+{
+//    while (!(USART2->SR & USART_FLAG_RXNE));
+//    return USART2->DR;
+    return 0;
+}
+
+
+int _read(int fd, char *buf, size_t cnt)
+{
+    *buf = getch();
+
+    return 1;
+}
+
+void putch(unsigned char c)
+{
+//    if (c == '\n') putch('\r');
+
+//    while (!(USART2->SR & USART_FLAG_TXE));
+//    USART2->DR = c;
+}
+
+void cgets(char *s, int bufsize)
+{
+    char *p;
+    int c;
+    int i;
+
+    for (i = 0; i < bufsize; i++) {
+        *(s+i) = 0;
+    }
+//    memset(s, 0, bufsize);
+
+    p = s;
+
+    for (p = s; p < s + bufsize-1;)
+    {
+        c = getch();
+        switch (c)
+        {
+        case '\r' :
+        case '\n' :
+            putch('\r');
+            putch('\n');
+            *p = '\n';
+            return;
+
+        case '\b' :
+            if (p > s)
+            {
+                *p-- = 0;
+                putch('\b');
+                putch(' ');
+                putch('\b');
+            }
+            break;
+
+        default :
+            putch(c);
+            *p++ = c;
+            break;
+        }
+    }
+    return;
+}
+
+int _write(int fd, const char *buf, size_t cnt)
+{
+    int i;
+//    uart_send("_write\r\n");
+
+    for (i = 0; i < cnt; i++)
+        putch(buf[i]);
+
+    return cnt;
+}
+
+/* Override fgets() in newlib with a version that does line editing */
+char *fgets(char *s, int bufsize, void *f)
+{
+//    uart_send("fgets\r\n");
+    cgets(s, bufsize);
+    return s;
+}