[mirror_edk2.git] / StdLib / LibC / Stdio / freopen.c

/** @file\r
    Implementation of freopen as declared in <stdio.h>.\r
\r
    Copyright (c) 2010, Intel Corporation. All rights reserved.<BR>\r
    This program and the accompanying materials are licensed and made available\r
    under the terms and conditions of the BSD License that accompanies this\r
    distribution.  The full text of the license may be found at\r
    http://opensource.org/licenses/bsd-license.php.\r
\r
    THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
    WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
    Copyright (c) 1990, 1993\r
    The Regents of the University of California.  All rights reserved.\r
\r
    This code is derived from software contributed to Berkeley by\r
    Chris Torek.\r
\r
    Redistribution and use in source and binary forms, with or without\r
    modification, are permitted provided that the following conditions\r
    are met:\r
      - Redistributions of source code must retain the above copyright\r
        notice, this list of conditions and the following disclaimer.\r
      - Redistributions in binary form must reproduce the above copyright\r
        notice, this list of conditions and the following disclaimer in the\r
        documentation and/or other materials provided with the distribution.\r
      - Neither the name of the University nor the names of its contributors\r
        may be used to endorse or promote products derived from this software\r
        without specific prior written permission.\r
\r
    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"\r
    AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE\r
    IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE\r
    ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE\r
    LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR\r
    CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF\r
    SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS\r
    INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN\r
    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)\r
    ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE\r
    POSSIBILITY OF SUCH DAMAGE.\r
\r
    NetBSD: freopen.c,v 1.14 2003/08/07 16:43:25 agc Exp\r
    freopen.c 8.1 (Berkeley) 6/4/93\r
**/\r
#include  <LibConfig.h>\r
#include  <sys/EfiCdefs.h>\r
\r
#include  <sys/types.h>\r
#include  <sys/stat.h>\r
\r
#include  <assert.h>\r
#include  <errno.h>\r
#include  <fcntl.h>\r
#include  <sys/EfiSysCall.h>\r
#include  <stdio.h>\r
#include  <stdlib.h>\r
#include  <wchar.h>\r
#include  "reentrant.h"\r
#include  "local.h"\r
\r
/*\r
 * Re-direct an existing, open (probably) file to some other file.\r
 * ANSI is written such that the original file gets closed if at\r
 * all possible, no matter what.\r
 */\r
FILE *\r
freopen(const char *file, const char *mode, FILE *fp)\r
{\r
  int f;\r
  int flags, isopen, oflags, sverrno, wantfd;\r
\r
  _DIAGASSERT(file != NULL);\r
  _DIAGASSERT(mode != NULL);\r
  _DIAGASSERT(fp != NULL);\r
\r
  if ((flags = __sflags(mode, &oflags)) == 0) {\r
    (void) fclose(fp);\r
    return (NULL);\r
  }\r
\r
  if (!__sdidinit)\r
    __sinit();\r
\r
  /*\r
   * There are actually programs that depend on being able to "freopen"\r
   * descriptors that weren't originally open.  Keep this from breaking.\r
   * Remember whether the stream was open to begin with, and which file\r
   * descriptor (if any) was associated with it.  If it was attached to\r
   * a descriptor, defer closing it; freopen("/dev/stdin", "r", stdin)\r
   * should work.  This is unnecessary if it was not a Unix file.\r
   */\r
  if (fp->_flags == 0) {\r
    fp->_flags = __SEOF;  /* hold on to it */\r
    isopen = 0;\r
    wantfd = -1;\r
  } else {\r
    /* flush the stream; ANSI doesn't require this. */\r
    if (fp->_flags & __SWR)\r
      (void) __sflush(fp);\r
    /* if close is NULL, closing is a no-op, hence pointless */\r
    isopen = fp->_close != NULL;\r
    if ((wantfd = fp->_file) < 0 && isopen) {\r
      (void) (*fp->_close)(fp->_cookie);\r
      isopen = 0;\r
    }\r
  }\r
\r
  /* Get a new descriptor to refer to the new file. */\r
  f = open(file, oflags, DEFFILEMODE);\r
  if (f < 0 && isopen) {\r
    /* If out of fd's close the old one and try again. */\r
    if (errno == ENFILE || errno == EMFILE) {\r
      (void) (*fp->_close)(fp->_cookie);\r
      isopen = 0;\r
      f = open(file, oflags, DEFFILEMODE);\r
    }\r
  }\r
  sverrno = errno;\r
\r
  /*\r
   * Finish closing fp.  Even if the open succeeded above, we cannot\r
   * keep fp->_base: it may be the wrong size.  This loses the effect\r
   * of any setbuffer calls, but stdio has always done this before.\r
   */\r
  if (isopen && f != wantfd)\r
    (void) (*fp->_close)(fp->_cookie);\r
  if (fp->_flags & __SMBF)\r
    free((char *)fp->_bf._base);\r
  fp->_w = 0;\r
  fp->_r = 0;\r
  fp->_p = NULL;\r
  fp->_bf._base = NULL;\r
  fp->_bf._size = 0;\r
  fp->_lbfsize = 0;\r
  if (HASUB(fp))\r
    FREEUB(fp);\r
  WCIO_FREE(fp);\r
  _UB(fp)._size = 0;\r
  if (HASLB(fp))\r
    FREELB(fp);\r
  fp->_lb._size = 0;\r
\r
  if (f < 0) {      /* did not get it after all */\r
    fp->_flags = 0;   /* set it free */\r
    errno = sverrno;  /* restore in case _close clobbered */\r
    return (NULL);\r
  }\r
\r
  if (oflags & O_NONBLOCK) {\r
    struct stat st;\r
    if (fstat(f, &st) == -1) {\r
      sverrno = errno;\r
      (void)close(f);\r
      errno = sverrno;\r
      return (NULL);\r
    }\r
    if (!S_ISREG(st.st_mode)) {\r
      (void)close(f);\r
      errno = EFTYPE;\r
      return (NULL);\r
    }\r
  }\r
\r
  /*\r
   * If reopening something that was open before on a real file, try\r
   * to maintain the descriptor.  Various C library routines (perror)\r
   * assume stderr is always fd STDERR_FILENO, even if being freopen'd.\r
   */\r
  if (wantfd >= 0 && f != wantfd) {\r
    if (dup2(f, wantfd) >= 0) {\r
      (void) close(f);\r
      f = wantfd;\r
    }\r
  }\r
\r
  fp->_flags = (unsigned short)flags;\r
  fp->_file = (short)f;\r
  fp->_cookie = fp;\r
  fp->_read = __sread;\r
  fp->_write = __swrite;\r
  fp->_seek = __sseek;\r
  fp->_close = __sclose;\r
\r
  /*\r
   * When reopening in append mode, even though we use O_APPEND,\r
   * we need to seek to the end so that ftell() gets the right\r
   * answer.  If the user then alters the seek pointer, or\r
   * the file extends, this will fail, but there is not much\r
   * we can do about this.  (We could set __SAPP and check in\r
   * fseek and ftell.)\r
   */\r
  if (oflags & O_APPEND)\r
    (void) __sseek((void *)fp, (fpos_t)0, SEEK_END);\r
  return (fp);\r
}\r
Commit	Line	Data
2aa62f2b	1	/** @file\r
	2	Implementation of freopen as declared in <stdio.h>.\r
	3	\r
	4	Copyright (c) 2010, Intel Corporation. All rights reserved.<BR>\r
	5	This program and the accompanying materials are licensed and made available\r
	6	under the terms and conditions of the BSD License that accompanies this\r
	7	distribution. The full text of the license may be found at\r
	8	http://opensource.org/licenses/bsd-license.php.\r
	9	\r
	10	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
	11	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
	12	\r
	13	Copyright (c) 1990, 1993\r
	14	The Regents of the University of California. All rights reserved.\r
	15	\r
	16	This code is derived from software contributed to Berkeley by\r
	17	Chris Torek.\r
	18	\r
	19	Redistribution and use in source and binary forms, with or without\r
	20	modification, are permitted provided that the following conditions\r
	21	are met:\r
	22	- Redistributions of source code must retain the above copyright\r
	23	notice, this list of conditions and the following disclaimer.\r
	24	- Redistributions in binary form must reproduce the above copyright\r
	25	notice, this list of conditions and the following disclaimer in the\r
	26	documentation and/or other materials provided with the distribution.\r
	27	- Neither the name of the University nor the names of its contributors\r
	28	may be used to endorse or promote products derived from this software\r
	29	without specific prior written permission.\r
	30	\r
	31	THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"\r
	32	AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE\r
	33	IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE\r
	34	ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE\r
	35	LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR\r
	36	CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF\r
	37	SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS\r
	38	INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN\r
	39	CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)\r
	40	ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE\r
	41	POSSIBILITY OF SUCH DAMAGE.\r
	42	\r
	43	NetBSD: freopen.c,v 1.14 2003/08/07 16:43:25 agc Exp\r
	44	freopen.c 8.1 (Berkeley) 6/4/93\r
	45	**/\r
	46	#include <LibConfig.h>\r
	47	#include <sys/EfiCdefs.h>\r
	48	\r
	49	#include <sys/types.h>\r
	50	#include <sys/stat.h>\r
	51	\r
	52	#include <assert.h>\r
	53	#include <errno.h>\r
	54	#include <fcntl.h>\r
	55	#include <sys/EfiSysCall.h>\r
	56	#include <stdio.h>\r
	57	#include <stdlib.h>\r
	58	#include <wchar.h>\r
	59	#include "reentrant.h"\r
	60	#include "local.h"\r
	61	\r
	62	/*\r
	63	* Re-direct an existing, open (probably) file to some other file.\r
	64	* ANSI is written such that the original file gets closed if at\r
65	* all possible, no matter what.\r
66	*/\r
67	FILE *\r
68	freopen(const char file, const char mode, FILE *fp)\r
69	{\r
70	int f;\r
71	int flags, isopen, oflags, sverrno, wantfd;\r
72	\r
73	_DIAGASSERT(file != NULL);\r
74	_DIAGASSERT(mode != NULL);\r
75	_DIAGASSERT(fp != NULL);\r
76	\r
77	if ((flags = __sflags(mode, &oflags)) == 0) {\r
78	(void) fclose(fp);\r
79	return (NULL);\r
80	}\r
81	\r
82	if (!__sdidinit)\r
83	__sinit();\r
84	\r
85	/*\r
86	* There are actually programs that depend on being able to "freopen"\r
87	* descriptors that weren't originally open. Keep this from breaking.\r
88	* Remember whether the stream was open to begin with, and which file\r
89	* descriptor (if any) was associated with it. If it was attached to\r
90	* a descriptor, defer closing it; freopen("/dev/stdin", "r", stdin)\r
91	* should work. This is unnecessary if it was not a Unix file.\r
92	*/\r
93	if (fp->_flags == 0) {\r
94	fp->_flags = __SEOF; /* hold on to it */\r
95	isopen = 0;\r
96	wantfd = -1;\r
97	} else {\r
98	/* flush the stream; ANSI doesn't require this. */\r
99	if (fp->_flags & __SWR)\r
100	(void) __sflush(fp);\r
101	/* if close is NULL, closing is a no-op, hence pointless */\r
102	isopen = fp->_close != NULL;\r
103	if ((wantfd = fp->_file) < 0 && isopen) {\r
104	(void) (*fp->_close)(fp->_cookie);\r
105	isopen = 0;\r
106	}\r
107	}\r
108	\r
109	/* Get a new descriptor to refer to the new file. */\r
110	f = open(file, oflags, DEFFILEMODE);\r
111	if (f < 0 && isopen) {\r
112	/* If out of fd's close the old one and try again. */\r
113	if (errno == ENFILE \|\| errno == EMFILE) {\r
114	(void) (*fp->_close)(fp->_cookie);\r
115	isopen = 0;\r
116	f = open(file, oflags, DEFFILEMODE);\r
117	}\r
118	}\r
119	sverrno = errno;\r
120	\r
121	/*\r
122	* Finish closing fp. Even if the open succeeded above, we cannot\r
123	* keep fp->_base: it may be the wrong size. This loses the effect\r
124	* of any setbuffer calls, but stdio has always done this before.\r
125	*/\r
126	if (isopen && f != wantfd)\r
127	(void) (*fp->_close)(fp->_cookie);\r
128	if (fp->_flags & __SMBF)\r
129	free((char *)fp->_bf._base);\r
130	fp->_w = 0;\r
131	fp->_r = 0;\r
132	fp->_p = NULL;\r
133	fp->_bf._base = NULL;\r
134	fp->_bf._size = 0;\r
135	fp->_lbfsize = 0;\r
136	if (HASUB(fp))\r
137	FREEUB(fp);\r
138	WCIO_FREE(fp);\r
139	_UB(fp)._size = 0;\r
140	if (HASLB(fp))\r
141	FREELB(fp);\r
142	fp->_lb._size = 0;\r
143	\r
144	if (f < 0) { /* did not get it after all */\r
145	fp->_flags = 0; /* set it free */\r
146	errno = sverrno; /* restore in case _close clobbered */\r
147	return (NULL);\r
148	}\r
149	\r
150	if (oflags & O_NONBLOCK) {\r
151	struct stat st;\r
152	if (fstat(f, &st) == -1) {\r
153	sverrno = errno;\r
154	(void)close(f);\r
155	errno = sverrno;\r
156	return (NULL);\r
157	}\r
158	if (!S_ISREG(st.st_mode)) {\r
159	(void)close(f);\r
160	errno = EFTYPE;\r
161	return (NULL);\r
162	}\r
163	}\r
164	\r
165	/*\r
166	* If reopening something that was open before on a real file, try\r
167	* to maintain the descriptor. Various C library routines (perror)\r
168	* assume stderr is always fd STDERR_FILENO, even if being freopen'd.\r
169	*/\r
170	if (wantfd >= 0 && f != wantfd) {\r
171	if (dup2(f, wantfd) >= 0) {\r
172	(void) close(f);\r
173	f = wantfd;\r
174	}\r
175	}\r
176	\r
177	fp->_flags = (unsigned short)flags;\r
178	fp->_file = (short)f;\r
179	fp->_cookie = fp;\r
180	fp->_read = __sread;\r
181	fp->_write = __swrite;\r
182	fp->_seek = __sseek;\r
183	fp->_close = __sclose;\r
184	\r
185	/*\r
186	* When reopening in append mode, even though we use O_APPEND,\r
187	* we need to seek to the end so that ftell() gets the right\r
188	* answer. If the user then alters the seek pointer, or\r
189	* the file extends, this will fail, but there is not much\r
190	* we can do about this. (We could set __SAPP and check in\r
191	* fseek and ftell.)\r
192	*/\r
193	if (oflags & O_APPEND)\r
194	(void) __sseek((void *)fp, (fpos_t)0, SEEK_END);\r
195	return (fp);\r
196	}\r