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Remove pre-2.2 Linux kernel support.

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This commit is contained in:
Joseph Myers
2012-05-14 14:11:02 +00:00
parent 1bfb72913b
commit ffb7875d03
40 changed files with 333 additions and 1447 deletions
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183
sysdeps/unix/sysv/linux/getcwd.c
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@ -38,27 +38,6 @@
#endif
#if __ASSUME_GETCWD_SYSCALL > 0
/* Kernel 2.1.92 introduced a third way to get the current working
directory: a syscall. We've got to be careful that even when
compiling under 2.1.92+ the libc still runs under older kernels. */
# define no_syscall_getcwd 0
# define have_new_dcache 1
#else
# if __NR_getcwd
/* Kernel 2.1.92 introduced a third way to get the current working
directory: a syscall. We've got to be careful that even when
compiling under 2.1.92+ the libc still runs under older kernels.
An additional problem is that the system call does not return
the path of directories longer than one page. */
static int no_syscall_getcwd;
static int have_new_dcache;
# else
# define no_syscall_getcwd 1
static int have_new_dcache = 1;
# endif
#endif
/* The "proc" filesystem provides an easy method to retrieve the value.
For each process, the corresponding directory contains a symbolic link
named `cwd'. Reading the content of this link immediate gives us the
@ -73,9 +52,6 @@ __getcwd (char *buf, size_t size)
int n;
char *result;
if (no_syscall_getcwd && !have_new_dcache)
return generic_getcwd (buf, size);
#ifndef NO_ALLOCATION
size_t alloc_size = size;
if (size == 0)
@ -101,138 +77,59 @@ __getcwd (char *buf, size_t size)
#endif
path = buf;
#if defined __NR_getcwd || __LINUX_GETCWD_SYSCALL > 0
if (!no_syscall_getcwd)
int retval;
retval = INLINE_SYSCALL (getcwd, 2, CHECK_STRING (path), alloc_size);
if (retval >= 0)
{
int retval;
#ifndef NO_ALLOCATION
if (buf == NULL && size == 0)
/* Ensure that the buffer is only as large as necessary. */
buf = realloc (path, (size_t) retval);
retval = INLINE_SYSCALL (getcwd, 2, CHECK_STRING (path), alloc_size);
if (retval >= 0)
{
# ifndef NO_ALLOCATION
if (buf == NULL && size == 0)
/* Ensure that the buffer is only as large as necessary. */
buf = realloc (path, (size_t) retval);
if (buf == NULL)
/* Either buf was NULL all along, or `realloc' failed but
we still have the original string. */
buf = path;
# endif
return buf;
}
/* The system call cannot handle paths longer than a page.
Neither can the magic symlink in /proc/self. Just use the
generic implementation right away. */
if (errno == ENAMETOOLONG)
{
# ifndef NO_ALLOCATION
if (buf == NULL && size == 0)
{
free (path);
path = NULL;
}
# endif
result = generic_getcwd (path, size);
# ifndef NO_ALLOCATION
if (result == NULL && buf == NULL && size != 0)
free (path);
# endif
return result;
}
# if __ASSUME_GETCWD_SYSCALL
/* It should never happen that the `getcwd' syscall failed because
the buffer is too small if we allocated the buffer ourselves
large enough. */
assert (errno != ERANGE || buf != NULL || size != 0);
# ifndef NO_ALLOCATION
if (buf == NULL)
/* Either buf was NULL all along, or `realloc' failed but
we still have the original string. */
buf = path;
#endif
return buf;
}
/* The system call cannot handle paths longer than a page.
Neither can the magic symlink in /proc/self. Just use the
generic implementation right away. */
if (errno == ENAMETOOLONG)
{
#ifndef NO_ALLOCATION
if (buf == NULL && size == 0)
{
free (path);
path = NULL;
}
#endif
result = generic_getcwd (path, size);
#ifndef NO_ALLOCATION
if (result == NULL && buf == NULL && size != 0)
free (path);
# endif
return NULL;
# else
if (errno == ENOSYS)
{
no_syscall_getcwd = 1;
have_new_dcache = 1; /* Now we will try the /proc method. */
}
else if (errno != ERANGE || buf != NULL)
{
# ifndef NO_ALLOCATION
if (buf == NULL)
free (path);
# endif
return NULL;
}
# endif
}
#endif
n = __readlink ("/proc/self/cwd", path, alloc_size - 1);
if (n != -1)
{
if (path[0] == '/')
{
if ((size_t) n >= alloc_size - 1)
{
#ifndef NO_ALLOCATION
if (buf == NULL)
free (path);
#endif
return NULL;
}
path[n] = '\0';
#ifndef NO_ALLOCATION
if (buf == NULL && size == 0)
/* Ensure that the buffer is only as large as necessary. */
buf = realloc (path, (size_t) n + 1);
if (buf == NULL)
/* Either buf was NULL all along, or `realloc' failed but
we still have the original string. */
buf = path;
#endif
return buf;
}
#ifndef have_new_dcache
else
have_new_dcache = 0;
#endif
return result;
}
#if __ASSUME_GETCWD_SYSCALL == 0
/* Set to have_new_dcache only if error indicates that proc doesn't
exist. */
if (errno != EACCES && errno != ENAMETOOLONG)
have_new_dcache = 0;
#endif
/* It should never happen that the `getcwd' syscall failed because
the buffer is too small if we allocated the buffer ourselves
large enough. */
assert (errno != ERANGE || buf != NULL || size != 0);
#ifndef NO_ALLOCATION
/* Don't put restrictions on the length of the path unless the user does. */
if (buf == NULL && size == 0)
{
free (path);
path = NULL;
}
#endif
result = generic_getcwd (path, size);
#ifndef NO_ALLOCATION
if (result == NULL && buf == NULL && size != 0)
if (buf == NULL)
free (path);
#endif
return result;
return NULL;
}
weak_alias (__getcwd, getcwd)