open_r.c

来自「FAT16 Filesystem on Philips LPC2000 seri」· C语言 代码 · 共 36 行

#include <reent.h>
#include <errno.h>
#include <devices.h>
#include <string.h>
#include <sysdefs.h>

int _open_r ( struct _reent *ptr, const char *file, int flags, int mode)
{
#ifdef HAS_MMC
int	i, len;
		// all devices must start with a name and name is bracketed with '/'.
	if (file[0] == '/') {
			// we might have a valid device name, search the table list.
		for (i=0; device_table_list [i].item; i++) {
			len = strlen(device_table_list[i].item->name);
			if (strncmp (device_table_list [i].item->name, &file[1], len) == 0) {
					// ensure trailing '/'.
				if (file[len+1] != '/') continue;
					// found it, now call the open.
					// device is called with device name removed.
				if (device_table_list[i].item->open) {
						// a function address appears to be there...
					return device_table_list [i].item->open( ptr, &file[len+2], flags, mode);
				}
			}
		}
	}
#endif
		// otherwise we get nasty about it..
	ptr->_errno = ENODEV;
	return -1;
}

// vi:nowrap