grub/kern/emu/misc.c
Colin Watson db2102a046 * kern/emu/misc.c (canonicalize_file_name): realpath can still
return NULL for various reasons even if it has a maximum-length
buffer: for example, there might be a symlink loop, or the path
might exceed PATH_MAX.  If this happens, return NULL.
2010-05-27 15:45:41 +01:00

313 lines
5.8 KiB
C

#include <config.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#ifdef HAVE_LIMITS_H
#include <limits.h>
#endif
#include <grub/mm.h>
#include <grub/err.h>
#include <grub/env.h>
#include <grub/types.h>
#include <grub/misc.h>
#include <grub/i18n.h>
#include <grub/time.h>
#include <grub/emu/misc.h>
int verbosity;
void
grub_util_warn (const char *fmt, ...)
{
va_list ap;
fprintf (stderr, _("%s: warn:"), program_name);
fprintf (stderr, " ");
va_start (ap, fmt);
vfprintf (stderr, fmt, ap);
va_end (ap);
fprintf (stderr, ".\n");
fflush (stderr);
}
void
grub_util_info (const char *fmt, ...)
{
if (verbosity > 0)
{
va_list ap;
fprintf (stderr, _("%s: info:"), program_name);
fprintf (stderr, " ");
va_start (ap, fmt);
vfprintf (stderr, fmt, ap);
va_end (ap);
fprintf (stderr, ".\n");
fflush (stderr);
}
}
void
grub_util_error (const char *fmt, ...)
{
va_list ap;
fprintf (stderr, _("%s: error:"), program_name);
fprintf (stderr, " ");
va_start (ap, fmt);
vfprintf (stderr, fmt, ap);
va_end (ap);
fprintf (stderr, ".\n");
exit (1);
}
void *
xmalloc (grub_size_t size)
{
void *p;
p = malloc (size);
if (! p)
grub_util_error ("out of memory");
return p;
}
void *
xrealloc (void *ptr, grub_size_t size)
{
ptr = realloc (ptr, size);
if (! ptr)
grub_util_error ("out of memory");
return ptr;
}
char *
xstrdup (const char *str)
{
size_t len;
char *newstr;
len = strlen (str);
newstr = (char *) xmalloc (len + 1);
memcpy (newstr, str, len + 1);
return newstr;
}
#ifndef HAVE_VASPRINTF
int
vasprintf (char **buf, const char *fmt, va_list ap)
{
/* Should be large enough. */
*buf = xmalloc (512);
return vsprintf (*buf, fmt, ap);
}
#endif
#ifndef HAVE_ASPRINTF
int
asprintf (char **buf, const char *fmt, ...)
{
int status;
va_list ap;
va_start (ap, fmt);
status = vasprintf (*buf, fmt, ap);
va_end (ap);
return status;
}
#endif
char *
xasprintf (const char *fmt, ...)
{
va_list ap;
char *result;
va_start (ap, fmt);
if (vasprintf (&result, fmt, ap) < 0)
{
if (errno == ENOMEM)
grub_util_error ("out of memory");
return NULL;
}
return result;
}
void
grub_exit (void)
{
exit (1);
}
grub_uint64_t
grub_get_time_ms (void)
{
struct timeval tv;
gettimeofday (&tv, 0);
return (tv.tv_sec * 1000 + tv.tv_usec / 1000);
}
grub_uint32_t
grub_get_rtc (void)
{
struct timeval tv;
gettimeofday (&tv, 0);
return (tv.tv_sec * GRUB_TICKS_PER_SECOND
+ (((tv.tv_sec % GRUB_TICKS_PER_SECOND) * 1000000 + tv.tv_usec)
* GRUB_TICKS_PER_SECOND / 1000000));
}
char *
canonicalize_file_name (const char *path)
{
char *ret;
#ifdef PATH_MAX
ret = xmalloc (PATH_MAX);
if (!realpath (path, ret))
return NULL;
#else
ret = realpath (path, NULL);
#endif
return ret;
}
#ifdef __CYGWIN__
/* Convert POSIX path to Win32 path,
remove drive letter, replace backslashes. */
static char *
get_win32_path (const char *path)
{
char winpath[PATH_MAX];
if (cygwin_conv_path (CCP_POSIX_TO_WIN_A, path, winpath, sizeof(winpath)))
grub_util_error ("cygwin_conv_path() failed");
int len = strlen (winpath);
int offs = (len > 2 && winpath[1] == ':' ? 2 : 0);
int i;
for (i = offs; i < len; i++)
if (winpath[i] == '\\')
winpath[i] = '/';
return xstrdup (winpath + offs);
}
#endif
/* This function never prints trailing slashes (so that its output
can be appended a slash unconditionally). */
char *
grub_make_system_path_relative_to_its_root (const char *path)
{
struct stat st;
char *p, *buf, *buf2, *buf3;
uintptr_t offset = 0;
dev_t num;
size_t len;
/* canonicalize. */
p = canonicalize_file_name (path);
if (p == NULL)
grub_util_error ("failed to get canonical path of %s", path);
len = strlen (p) + 1;
buf = xstrdup (p);
free (p);
if (stat (buf, &st) < 0)
grub_util_error ("cannot stat %s: %s", buf, strerror (errno));
buf2 = xstrdup (buf);
num = st.st_dev;
/* This loop sets offset to the number of chars of the root
directory we're inspecting. */
while (1)
{
p = strrchr (buf, '/');
if (p == NULL)
/* This should never happen. */
grub_util_error ("FIXME: no / in buf. (make_system_path_relative_to_its_root)");
if (p != buf)
*p = 0;
else
*++p = 0;
if (stat (buf, &st) < 0)
grub_util_error ("cannot stat %s: %s", buf, strerror (errno));
/* buf is another filesystem; we found it. */
if (st.st_dev != num)
{
/* offset == 0 means path given is the mount point.
This works around special-casing of "/" in Un*x. This function never
prints trailing slashes (so that its output can be appended a slash
unconditionally). Each slash in is considered a preceding slash, and
therefore the root directory is an empty string. */
if (offset == 0)
{
free (buf);
free (buf2);
return xstrdup ("");
}
else
break;
}
offset = p - buf;
/* offset == 1 means root directory. */
if (offset == 1)
{
/* Include leading slash. */
offset = 0;
break;
}
}
free (buf);
buf3 = xstrdup (buf2 + offset);
free (buf2);
#ifdef __CYGWIN__
if (st.st_dev != (DEV_CYGDRIVE_MAJOR << 16))
{
/* Reached some mount point not below /cygdrive.
GRUB does not know Cygwin's emulated mounts,
convert to Win32 path. */
grub_util_info ("Cygwin path = %s\n", buf3);
char * temp = get_win32_path (buf3);
free (buf3);
buf3 = temp;
}
#endif
/* Remove trailing slashes, return empty string if root directory. */
len = strlen (buf3);
while (len > 0 && buf3[len - 1] == '/')
{
buf3[len - 1] = '\0';
len--;
}
return buf3;
}