Move stdio implementation details around a little.
Change-Id: I24594426d5479bdd55cbef0ab1b7d76c249dbd0c
diff --git a/libc/stdio/stdio.cpp b/libc/stdio/stdio.cpp
new file mode 100644
index 0000000..1ea3ef5
--- /dev/null
+++ b/libc/stdio/stdio.cpp
@@ -0,0 +1,227 @@
+/* $OpenBSD: findfp.c,v 1.15 2013/12/17 16:33:27 deraadt Exp $ */
+/*-
+ * Copyright (c) 1990, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Chris Torek.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <stdio.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+#include "local.h"
+#include "glue.h"
+#include "private/thread_private.h"
+
+#define ALIGNBYTES (sizeof(uintptr_t) - 1)
+#define ALIGN(p) (((uintptr_t)(p) + ALIGNBYTES) &~ ALIGNBYTES)
+
+#define NDYNAMIC 10 /* add ten more whenever necessary */
+
+#define std(flags, file) \
+ {0,0,0,flags,file,{0,0},0,__sF+file,__sclose,__sread,__sseek,__swrite, \
+ {(unsigned char *)(__sFext+file), 0},NULL,0,{0},{0},{0,0},0,0}
+
+_THREAD_PRIVATE_MUTEX(__sfp_mutex);
+
+// TODO: when we no longer have to support both clang and GCC, we can simplify all this.
+#define SBUF_INIT {0,0}
+#if defined(__LP64__)
+#define MBSTATE_T_INIT {{0},{0}}
+#else
+#define MBSTATE_T_INIT {{0}}
+#endif
+#define WCHAR_IO_DATA_INIT {MBSTATE_T_INIT,MBSTATE_T_INIT,{0},0,0}
+
+static struct __sfileext __sFext[3] = {
+ { SBUF_INIT, WCHAR_IO_DATA_INIT, PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP, false },
+ { SBUF_INIT, WCHAR_IO_DATA_INIT, PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP, false },
+ { SBUF_INIT, WCHAR_IO_DATA_INIT, PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP, false },
+};
+
+// __sF is exported for backwards compatibility. Until M, we didn't have symbols
+// for stdin/stdout/stderr; they were macros accessing __sF.
+FILE __sF[3] = {
+ std(__SRD, STDIN_FILENO),
+ std(__SWR, STDOUT_FILENO),
+ std(__SWR|__SNBF, STDERR_FILENO),
+};
+
+FILE* stdin = &__sF[0];
+FILE* stdout = &__sF[1];
+FILE* stderr = &__sF[2];
+
+struct glue __sglue = { NULL, 3, __sF };
+static struct glue* lastglue = &__sglue;
+
+static glue* moreglue(int n) {
+ static FILE empty;
+
+ char* data = new char[sizeof(glue) + ALIGNBYTES + n * sizeof(FILE) + n * sizeof(__sfileext)];
+ if (data == nullptr) return nullptr;
+
+ glue* g = reinterpret_cast<glue*>(data);
+ FILE* p = reinterpret_cast<FILE*>(ALIGN(data + sizeof(*g)));
+ __sfileext* pext = reinterpret_cast<__sfileext*>(ALIGN(data + sizeof(*g)) + n * sizeof(FILE));
+ g->next = NULL;
+ g->niobs = n;
+ g->iobs = p;
+ while (--n >= 0) {
+ *p = empty;
+ _FILEEXT_SETUP(p, pext);
+ p++;
+ pext++;
+ }
+ return g;
+}
+
+/*
+ * Find a free FILE for fopen et al.
+ */
+FILE* __sfp(void) {
+ FILE *fp;
+ int n;
+ struct glue *g;
+
+ _THREAD_PRIVATE_MUTEX_LOCK(__sfp_mutex);
+ for (g = &__sglue; g != NULL; g = g->next) {
+ for (fp = g->iobs, n = g->niobs; --n >= 0; fp++)
+ if (fp->_flags == 0)
+ goto found;
+ }
+
+ /* release lock while mallocing */
+ _THREAD_PRIVATE_MUTEX_UNLOCK(__sfp_mutex);
+ if ((g = moreglue(NDYNAMIC)) == NULL)
+ return (NULL);
+ _THREAD_PRIVATE_MUTEX_LOCK(__sfp_mutex);
+ lastglue->next = g;
+ lastglue = g;
+ fp = g->iobs;
+found:
+ fp->_flags = 1; /* reserve this slot; caller sets real flags */
+ _THREAD_PRIVATE_MUTEX_UNLOCK(__sfp_mutex);
+ fp->_p = NULL; /* no current pointer */
+ fp->_w = 0; /* nothing to read or write */
+ fp->_r = 0;
+ fp->_bf._base = NULL; /* no buffer */
+ fp->_bf._size = 0;
+ fp->_lbfsize = 0; /* not line buffered */
+ fp->_file = -1; /* no file */
+/* fp->_cookie = <any>; */ /* caller sets cookie, _read/_write etc */
+ fp->_lb._base = NULL; /* no line buffer */
+ fp->_lb._size = 0;
+ _FILEEXT_INIT(fp);
+ return (fp);
+}
+
+extern "C" __LIBC_HIDDEN__ void __libc_stdio_cleanup(void) {
+ /* (void) _fwalk(fclose); */
+ (void) _fwalk(__sflush); /* `cheating' */
+}
+
+int fclose(FILE* fp) {
+ if (fp->_flags == 0) {
+ // Already freed!
+ errno = EBADF;
+ return EOF;
+ }
+
+ FLOCKFILE(fp);
+ WCIO_FREE(fp);
+ int r = fp->_flags & __SWR ? __sflush(fp) : 0;
+ if (fp->_close != NULL && (*fp->_close)(fp->_cookie) < 0) {
+ r = EOF;
+ }
+ if (fp->_flags & __SMBF) free(fp->_bf._base);
+ if (HASUB(fp)) FREEUB(fp);
+ if (HASLB(fp)) FREELB(fp);
+
+ // Poison this FILE so accesses after fclose will be obvious.
+ fp->_file = -1;
+ fp->_r = fp->_w = 0;
+
+ // Release this FILE for reuse.
+ fp->_flags = 0;
+ FUNLOCKFILE(fp);
+ return (r);
+}
+
+int fileno(FILE* fp) {
+ FLOCKFILE(fp);
+ int result = fileno_unlocked(fp);
+ FUNLOCKFILE(fp);
+ return result;
+}
+
+// Small standard I/O/seek/close functions.
+// These maintain the `known seek offset' for seek optimisation.
+int __sread(void* cookie, char* buf, int n) {
+ FILE* fp = reinterpret_cast<FILE*>(cookie);
+ int ret = TEMP_FAILURE_RETRY(read(fp->_file, buf, n));
+ // If the read succeeded, update the current offset.
+ if (ret >= 0) {
+ fp->_offset += ret;
+ } else {
+ fp->_flags &= ~__SOFF; // Paranoia.
+ }
+ return ret;
+}
+
+int __swrite(void* cookie, const char* buf, int n) {
+ FILE* fp = reinterpret_cast<FILE*>(cookie);
+ if (fp->_flags & __SAPP) {
+ (void) TEMP_FAILURE_RETRY(lseek(fp->_file, 0, SEEK_END));
+ }
+ fp->_flags &= ~__SOFF; // In case FAPPEND mode is set.
+ return TEMP_FAILURE_RETRY(write(fp->_file, buf, n));
+}
+
+// TODO: _FILE_OFFSET_BITS=64.
+fpos_t __sseek(void* cookie, fpos_t offset, int whence) {
+ FILE* fp = reinterpret_cast<FILE*>(cookie);
+ off_t ret = TEMP_FAILURE_RETRY(lseek(fp->_file, offset, whence));
+ if (ret == -1) {
+ fp->_flags &= ~__SOFF;
+ } else {
+ fp->_flags |= __SOFF;
+ fp->_offset = ret;
+ }
+ return ret;
+}
+
+int __sclose(void* cookie) {
+ FILE* fp = reinterpret_cast<FILE*>(cookie);
+ return close(fp->_file);
+}