aboutsummaryrefslogtreecommitdiff
path: root/newlib/libc/stdio/fopencookie.c
diff options
context:
space:
mode:
authorEric Blake <eblake@redhat.com>2007-06-04 18:10:17 +0000
committerEric Blake <eblake@redhat.com>2007-06-04 18:10:17 +0000
commit17c61d6a2c4868260c1ef3043e03f86de14f6a08 (patch)
treec795768b8f7d0fa0048f5bd77f6dad9c5ce069e1 /newlib/libc/stdio/fopencookie.c
parent6a3b4eb69a7d2b1e1c19a8baef42ce6dc3d61a86 (diff)
downloadnewlib-17c61d6a2c4868260c1ef3043e03f86de14f6a08.zip
newlib-17c61d6a2c4868260c1ef3043e03f86de14f6a08.tar.gz
newlib-17c61d6a2c4868260c1ef3043e03f86de14f6a08.tar.bz2
Implement funopen, fopencookie.
* libc/include/sys/reent.h (struct __sFILE, struct __sFILE64): Switch to reentrant callbacks. * libc/include/stdio.h (funopen): Fix declaration. (fopencookie): Declare. * libc/stdio/local.h (__sread, __swrite, __sseek, __sclose) (__sseek64, __swrite64): Fix prototypes. [__SCLE]: Pull in setmode declaration. * libc/stdio/stdio.c (__sread, __swrite, __sseek, __sclose): Fix reentrancy. * libc/stdio64/stdio64.c (__sseek64_r, __swrite64_r): Delete. (__sseek64, __swrite64): Fix reentrancy. * libc/stdio/fseek.c (_fseek_r): Account for overflow, and fix reentrancy. * libc/stdio/ftell.c (_ftell_r): Likewise. * libc/stdio/flags.c (__sflags): Don't lose __SAPP on "a+". * libc/stdio/fclose.c (_fclose_r): Fix reentrancy. * libc/stdio/freopen.c (_freopen_r): Likewise. * libc/stdio/fvwrite.c (__sfvwrite_r): Likewise. * libc/stdio/refill.c (__srefill_r): Likewise. * libc/stdio/siscanf.c (eofread): Likewise. * libc/stdio/sscanf.c (eofread): Likewise. * libc/stdio/vsiscanf.c (eofread1): Likewise. * libc/stdio/vsscanf.c (eofread1): Likewise. * libc/stdio64/freopen64.c (_freopen64_r): Likewise. * libc/stdio64/fseeko64.c (_fseeko64_r): Likewise. * libc/stdio64/ftello64.c (_ftello64_r): Likewise. * libc/stdio/fflush.c (fflush): Improve reentrancy, although more could be fixed. * libc/stdio/fopencookie.c (_fopencookie_r, fopencookie): New file. * libc/stdio/funopen.c (_funopen_r, funopen): New file. * libc/stdio/Makefile.am (ELIX_4_SOURCES, CHEWOUT_FILES): Build new files. * libc/stdio/Makefile.in: Regenerate.
Diffstat (limited to 'newlib/libc/stdio/fopencookie.c')
-rw-r--r--newlib/libc/stdio/fopencookie.c258
1 files changed, 258 insertions, 0 deletions
diff --git a/newlib/libc/stdio/fopencookie.c b/newlib/libc/stdio/fopencookie.c
new file mode 100644
index 0000000..581441b
--- /dev/null
+++ b/newlib/libc/stdio/fopencookie.c
@@ -0,0 +1,258 @@
+/* Copyright (C) 2007 Eric Blake
+ * Permission to use, copy, modify, and distribute this software
+ * is freely granted, provided that this notice is preserved.
+ */
+
+/*
+FUNCTION
+<<fopencookie>>---open a stream with custom callbacks
+
+INDEX
+ fopencookie
+
+ANSI_SYNOPSIS
+ #include <stdio.h>
+ typedef ssize_t (*cookie_read_function_t)(void *_cookie, char *_buf,
+ size_t _n);
+ typedef ssize_t (*cookie_write_function_t)(void *_cookie,
+ const char *_buf, size_t _n);
+ typedef int (*cookie_seek_function_t)(void *_cookie, off_t *_off,
+ int _whence);
+ typedef int (*cookie_close_function_t)(void *_cookie);
+ typedef struct
+ {
+ cookie_read_function_t *read;
+ cookie_write_function_t *write;
+ cookie_seek_function_t *seek;
+ cookie_close_function_t *close;
+ } cookie_io_functions_t;
+ FILE *fopencookie(const void *<[cookie]>, const char *<[mode]>,
+ cookie_io_functions_t <[functions]>);
+
+DESCRIPTION
+<<fopencookie>> creates a <<FILE>> stream where I/O is performed using
+custom callbacks. The stream is opened with <[mode]> treated as in
+<<fopen>>. The callbacks <[functions.read]> and <[functions.write]>
+may only be NULL when <[mode]> does not require them.
+
+<[functions.read]> should return -1 on failure, or else the number of
+bytes read (0 on EOF). It is similar to <<read>>, except that
+<[cookie]> will be passed as the first argument.
+
+<[functions.write]> should return -1 on failure, or else the number of
+bytes written. It is similar to <<write>>, except that <[cookie]>
+will be passed as the first argument.
+
+<[functions.seek]> should return -1 on failure, and 0 on success, with
+*<[_off]> set to the current file position. It is a cross between
+<<lseek>> and <<fseek>>, with the <[_whence]> argument interpreted in
+the same manner. A NULL <[functions.seek]> makes the stream behave
+similarly to a pipe in relation to stdio functions that require
+positioning.
+
+<[functions.close]> should return -1 on failure, or 0 on success. It
+is similar to <<close>>, except that <[cookie]> will be passed as the
+first argument. A NULL <[functions.close]> merely flushes all data
+then lets <<fclose>> succeed. A failed close will still invalidate
+the stream.
+
+Read and write I/O functions are allowed to change the underlying
+buffer on fully buffered or line buffered streams by calling
+<<setvbuf>>. They are also not required to completely fill or empty
+the buffer. They are not, however, allowed to change streams from
+unbuffered to buffered or to change the state of the line buffering
+flag. They must also be prepared to have read or write calls occur on
+buffers other than the one most recently specified.
+
+RETURNS
+The return value is an open FILE pointer on success. On error,
+<<NULL>> is returned, and <<errno>> will be set to EINVAL if a
+function pointer is missing or <[mode]> is invalid, ENOMEM if the
+stream cannot be created, or EMFILE if too many streams are already
+open.
+
+PORTABILITY
+This function is a newlib extension, copying the prototype from Linux.
+It is not portable. See also the <<funopen>> interface from BSD.
+
+Supporting OS subroutines required: <<sbrk>>.
+*/
+
+#include <stdio.h>
+#include <errno.h>
+#include <sys/lock.h>
+#include "local.h"
+
+typedef struct fccookie {
+ void *cookie;
+ FILE *fp;
+ cookie_read_function_t *readfn;
+ cookie_write_function_t *writefn;
+ cookie_seek_function_t *seekfn;
+ cookie_close_function_t *closefn;
+} fccookie;
+
+static _READ_WRITE_RETURN_TYPE
+_DEFUN(fcreader, (ptr, cookie, buf, n),
+ struct _reent *ptr _AND
+ void *cookie _AND
+ char *buf _AND
+ int n)
+{
+ int result;
+ fccookie *c = (fccookie *) cookie;
+ errno = 0;
+ if ((result = c->readfn (c->cookie, buf, n)) < 0 && errno)
+ ptr->_errno = errno;
+ return result;
+}
+
+static _READ_WRITE_RETURN_TYPE
+_DEFUN(fcwriter, (ptr, cookie, buf, n),
+ struct _reent *ptr _AND
+ void *cookie _AND
+ const char *buf _AND
+ int n)
+{
+ int result;
+ fccookie *c = (fccookie *) cookie;
+ if (c->fp->_flags & __SAPP && c->fp->_seek)
+ {
+#ifdef __LARGE64_FILES
+ c->fp->_seek64 (ptr, c->fp->_cookie, 0, SEEK_END);
+#else
+ c->fp->_seek (ptr, c->fp->_cookie, 0, SEEK_END);
+#endif
+ }
+ errno = 0;
+ if ((result = c->writefn (c->cookie, buf, n)) < 0 && errno)
+ ptr->_errno = errno;
+ return result;
+}
+
+static _fpos_t
+_DEFUN(fcseeker, (ptr, cookie, off, whence),
+ struct _reent *ptr _AND
+ void *cookie _AND
+ _fpos_t pos _AND
+ int whence)
+{
+ fccookie *c = (fccookie *) cookie;
+#ifndef __LARGE64_FILES
+ off_t offset = (off_t) pos;
+#else /* __LARGE64_FILES */
+ _off64_t offset = (_off64_t) pos;
+#endif /* __LARGE64_FILES */
+
+ errno = 0;
+ if (c->seekfn (c->cookie, &offset, whence) < 0 && errno)
+ ptr->_errno = errno;
+#ifdef __LARGE64_FILES
+ else if ((_fpos_t)offset != offset)
+ {
+ ptr->_errno = EOVERFLOW;
+ offset = -1;
+ }
+#endif /* __LARGE64_FILES */
+ return (_fpos_t) offset;
+}
+
+#ifdef __LARGE64_FILES
+static _fpos64_t
+_DEFUN(fcseeker64, (ptr, cookie, off, whence),
+ struct _reent *ptr _AND
+ void *cookie _AND
+ _fpos64_t pos _AND
+ int whence)
+{
+ _off64_t offset;
+ fccookie *c = (fccookie *) cookie;
+ errno = 0;
+ if (c->seekfn (c->cookie, &offset, whence) < 0 && errno)
+ ptr->_errno = errno;
+ return (_fpos64_t) offset;
+}
+#endif /* __LARGE64_FILES */
+
+static int
+_DEFUN(fccloser, (ptr, cookie),
+ struct _reent *ptr _AND
+ void *cookie)
+{
+ int result = 0;
+ fccookie *c = (fccookie *) cookie;
+ if (c->closefn)
+ {
+ errno = 0;
+ if ((result = c->closefn (c->cookie)) < 0 && errno)
+ ptr->_errno = errno;
+ }
+ _free_r (ptr, c);
+ return result;
+}
+
+FILE *
+_DEFUN(_fopencookie_r, (ptr, cookie, mode, functions),
+ struct _reent *ptr _AND
+ void *cookie _AND
+ const char *mode _AND
+ cookie_io_functions_t functions)
+{
+ FILE *fp;
+ fccookie *c;
+ int flags;
+ int dummy;
+
+ if ((flags = __sflags (ptr, mode, &dummy)) == 0)
+ return NULL;
+ if (((flags & (__SRD | __SRW)) && !functions.read)
+ || ((flags & (__SWR | __SRW)) && !functions.write))
+ {
+ ptr->_errno = EINVAL;
+ return NULL;
+ }
+ if ((fp = __sfp (ptr)) == NULL)
+ return NULL;
+ if ((c = (fccookie *) _malloc_r (ptr, sizeof *c)) == NULL)
+ {
+ __sfp_lock_acquire ();
+ fp->_flags = 0; /* release */
+#ifndef __SINGLE_THREAD__
+ __lock_close_recursive (fp->_lock);
+#endif
+ __sfp_lock_release ();
+ return NULL;
+ }
+
+ _flockfile (fp);
+ fp->_file = -1;
+ fp->_flags = flags;
+ c->cookie = cookie;
+ c->fp = fp;
+ fp->_cookie = c;
+ c->readfn = functions.read;
+ fp->_read = fcreader;
+ c->writefn = functions.write;
+ fp->_write = fcwriter;
+ c->seekfn = functions.seek;
+ fp->_seek = functions.seek ? fcseeker : NULL;
+#ifdef __LARGE64_FILES
+ fp->_seek64 = functions.seek ? fcseeker64 : NULL;
+ fp->_flags |= __SL64;
+#endif
+ c->closefn = functions.close;
+ fp->_close = fccloser;
+ _funlockfile (fp);
+ return fp;
+}
+
+#ifndef _REENT_ONLY
+FILE *
+_DEFUN(fopencookie, (cookie, mode, functions),
+ void *cookie _AND
+ const char *mode _AND
+ cookie_io_functions_t functions)
+{
+ return _fopencookie_r (_REENT, cookie, mode, functions);
+}
+#endif /* !_REENT_ONLY */