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#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;
}
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