[FFmpeg-devel] [PATCH] lavu: add snprintf(), vsnprint() and strtod() replacements for MS runtime.
Ronald S. Bultje
rsbultje at gmail.com
Mon Aug 27 23:00:37 CEST 2012
From: "Ronald S. Bultje" <rsbultje at gmail.com>
---
compat/snprintf.c | 64 +++++++++++++++++++++++++++++++++++++
compat/snprintf.h | 46 +++++++++++++++++++++++++++
compat/strtod.c | 92 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
compat/strtod.h | 37 ++++++++++++++++++++++
configure | 26 +++++++++++++++
libavutil/Makefile | 3 ++
6 files changed, 268 insertions(+)
create mode 100644 compat/snprintf.c
create mode 100644 compat/snprintf.h
create mode 100644 compat/strtod.c
create mode 100644 compat/strtod.h
diff --git a/compat/snprintf.c b/compat/snprintf.c
new file mode 100644
index 0000000..c54c8e2
--- /dev/null
+++ b/compat/snprintf.c
@@ -0,0 +1,64 @@
+/*
+ * C99-compatible snprintf() and vsnprintf() implementations
+ * Copyright (c) 2012 Ronald S. Bultje <rsbultje at gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <limits.h>
+#include <string.h>
+
+#include "libavutil/error.h"
+#include "snprintf.h"
+
+#undef snprintf
+int avpriv_snprintf(char *restrict s, size_t n, const char *restrict fmt, ...)
+{
+ va_list ap;
+ int ret;
+
+ va_start(ap, fmt);
+ ret = avpriv_vsnprintf(s, n, fmt, ap);
+ va_end(ap);
+
+ return ret;
+}
+
+#undef vsnprintf
+int avpriv_vsnprintf(char *restrict s, size_t n, const char *restrict fmt,
+ va_list ap)
+{
+ int ret;
+
+ if (n == 0)
+ return 0;
+ else if (n > INT_MAX)
+ return AVERROR(EINVAL);
+
+ /* we use n - 1 here because if the buffer is not big enough, the MS
+ * runtime libraries don't add a terminating zero at the end. MSDN
+ * recommends to provide _snprintf/_vsnprintf() a buffer size that
+ * is one less than the actual buffer, and zero it before calling
+ * _snprintf/_vsnprintf() to workaround this problem.
+ * See http://msdn.microsoft.com/en-us/library/1kt27hek(v=vs.80).aspx */
+ memset(s, 0, n);
+ ret = vsnprintf(s, n - 1, fmt, ap);
+ if (ret == -1)
+ ret = n;
+
+ return ret;
+}
diff --git a/compat/snprintf.h b/compat/snprintf.h
new file mode 100644
index 0000000..60c198b
--- /dev/null
+++ b/compat/snprintf.h
@@ -0,0 +1,46 @@
+/*
+ * C99-compatible snprintf() and vsnprintf() implementations
+ * Copyright (c) 2012 Ronald S. Bultje <rsbultje at gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCOMPAT_SNPRINTF_H
+#define AVCOMPAT_SNPRINTF_H
+
+#include <stdarg.h>
+#include <stdio.h>
+
+/*
+ * snprintf() on MSVCRT returns -1 (instead of required buffer length)
+ * if the input buffer isn't big enough. Also, if the required buffer
+ * length is exactly identical to the input buffer size, or if the
+ * return value is -1 because the input buffer isn't big enough, MSVCRT
+ * will fail to NULL-terminate the output buffer. vsnprintf() has the
+ * same issue.
+ *
+ * Thus, provide our own fallback wrappers with correct behaviour.
+ */
+#undef snprintf
+#define snprintf avpriv_snprintf
+int snprintf(char *restrict s, size_t n, const char *restrict format, ...);
+
+#undef vsnprintf
+#define vsnprintf avpriv_vsnprintf
+int vsnprintf(char *restrict s, size_t n, const char *restrict format, va_list ap);
+
+#endif /* AVCOMPAT_SNPRINTF_H */
diff --git a/compat/strtod.c b/compat/strtod.c
new file mode 100644
index 0000000..149d18a
--- /dev/null
+++ b/compat/strtod.c
@@ -0,0 +1,92 @@
+/*
+ * C99-compatible strtod() implementation
+ * Copyright (c) 2012 Ronald S. Bultje <rsbultje at gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <ctype.h>
+#include <limits.h>
+
+#include "libavutil/avstring.h"
+#include "libavutil/mathematics.h"
+#include "strtod.h"
+
+static char *check_nan_suffix(char *s)
+{
+ char *start = s;
+
+ if (*s++ != '(')
+ return start;
+
+ while ((*s >= 'a' && *s <= 'z') || (*s >= 'A' && *s <= 'Z') ||
+ (*s >= '0' && *s <= '9') || *s == '_')
+ s++;
+
+ return *s == ')' ? s + 1 : start;
+}
+
+#undef strtod
+double avpriv_strtod(char *restrict nptr, char **restrict endptr)
+{
+ char *end;
+ double res;
+
+ /* Skip leading spaces */
+ while (isspace(*nptr))
+ nptr++;
+
+ if (!av_strncasecmp(nptr, "infinity", 8)) {
+ end = nptr + 8;
+ res = INFINITY;
+ } else if (!av_strncasecmp(nptr, "inf", 3)) {
+ end = nptr + 3;
+ res = INFINITY;
+ } else if (!av_strncasecmp(nptr, "+infinity", 9)) {
+ end = nptr + 9;
+ res = INFINITY;
+ } else if (!av_strncasecmp(nptr, "+inf", 4)) {
+ end = nptr + 4;
+ res = INFINITY;
+ } else if (!av_strncasecmp(nptr, "-infinity", 9)) {
+ end = nptr + 9;
+ res = -INFINITY;
+ } else if (!av_strncasecmp(nptr, "-inf", 4)) {
+ end = nptr + 4;
+ res = -INFINITY;
+ } else if (!av_strncasecmp(nptr, "nan", 3)) {
+ end = check_nan_suffix(nptr + 3);
+ res = NAN;
+ } else if (!av_strncasecmp(nptr, "+nan", 4) ||
+ !av_strncasecmp(nptr, "-nan", 4)) {
+ end = check_nan_suffix(nptr + 4);
+ res = NAN;
+ } else if (!av_strncasecmp(nptr, "0x", 2) ||
+ !av_strncasecmp(nptr, "-0x", 3) ||
+ !av_strncasecmp(nptr, "+0x", 3)) {
+ /* FIXME this doesn't handle exponents, non-integers (float/double)
+ * and numbers too large for long long */
+ res = strtoll(nptr, &end, 16);
+ } else {
+ res = strtod(nptr, &end);
+ }
+
+ if (endptr)
+ *endptr = end;
+
+ return res;
+}
diff --git a/compat/strtod.h b/compat/strtod.h
new file mode 100644
index 0000000..985bf4d
--- /dev/null
+++ b/compat/strtod.h
@@ -0,0 +1,37 @@
+/*
+ * C99-compatible strtod() implementation
+ * Copyright (c) 2012 Ronald S. Bultje <rsbultje at gmail.com>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef AVCOMPAT_STRTOD_H
+#define AVCOMPAT_STRTOD_H
+
+#include <stdlib.h>
+
+/*
+ * strtod() on MSVCRT doesn't handle strings like 'inf' or 'nan'. Also,
+ * it doesn't handle "0x" prefixes for hexadecimal input.
+ *
+ * Thus, provide our own fallback wrapper with correct behaviour.
+ */
+#undef strtod
+#define strtod avpriv_strtod
+double strtod(char *restrict nptr, char **restrict endptr);
+
+#endif /* AVCOMPAT_STRTOD_H */
diff --git a/configure b/configure
index 0b95927..16a325a 100755
--- a/configure
+++ b/configure
@@ -1031,6 +1031,11 @@ cp_if_changed(){
cp -f "$1" "$2"
}
+force_include(){
+ flag=$(eval printf '%s%s\\n' '$FORCE_INC' $1)
+ append CFLAGS "$flag"
+}
+
# CONFIG_LIST contains configurable options, while HAVE_LIST is for
# system-dependent things.
@@ -1228,6 +1233,7 @@ HAVE_LIST="
asm_types_h
attribute_may_alias
attribute_packed
+ broken_strtod
cbrtf
clock_gettime
closesocket
@@ -1314,6 +1320,7 @@ HAVE_LIST="
setrlimit
Sleep
sndio_h
+ snprintf
socklen_t
soundcard_h
strerror_r
@@ -2025,6 +2032,7 @@ CC_O='-o $@'
CXX_C='-c'
CXX_O='-o $@'
LD_O='-o $@'
+FORCE_INC="-include"
HOSTCC_C='-c'
HOSTCC_O='-o $@'
@@ -3344,6 +3352,7 @@ check_func mmap
check_func ${malloc_prefix}posix_memalign && enable posix_memalign
check_func_headers malloc.h _aligned_malloc && enable aligned_malloc
check_func setrlimit
+check_func snprintf
check_func strerror_r
check_func strptime
check_func sched_getaffinity
@@ -3364,6 +3373,15 @@ check_func_headers windows.h Sleep
check_func_headers windows.h VirtualAlloc
check_func_headers glob.h glob
+# Check for MSVCRT; it has a broken strtod() that can't parse some input.
+# Use old dos symbol to detect it. If we are on mingw, it already provides
+# its own replacement and we don't need to redo that.
+if check_func _get_doserrno; then
+ if test $target_os != mingw32; then
+ enable broken_strtod
+ fi
+fi
+
check_header dlfcn.h
check_header dxva.h
check_header dxva2api.h -D_WIN32_WINNT=0x0600
@@ -3735,6 +3753,14 @@ elif enabled pathscale; then
add_cflags -fstrict-overflow -OPT:wrap_around_unsafe_opt=OFF
fi
+# If a missing snprintf/broken strtod is detected, force-include headers
+# that override prototypes and define it to a prefixed one implemented in
+# libavutil. We do this at the end since -I flags aren't set in configure,
+# and any additional check_cflags() beyond here will thus fail (because
+# it can't find these files, because the -I$(srcdir) wasn't set).
+enabled snprintf || force_include compat/snprintf.h
+disabled broken_strtod || force_include compat/strtod.h
+
enabled_any $THREADS_LIST && enable threads
check_deps $CONFIG_LIST \
diff --git a/libavutil/Makefile b/libavutil/Makefile
index ef1f658..bd569ec 100644
--- a/libavutil/Makefile
+++ b/libavutil/Makefile
@@ -94,6 +94,9 @@ OBJS = adler32.o \
utils.o \
xtea.o \
+OBJS-$(!HAVE_SNPRINTF) += ../compat/snprintf.o
+OBJS-$(HAVE_BROKEN_STRTOD) += ../compat/strtod.o
+
TESTPROGS = adler32 \
aes \
avstring \
--
1.7.11.5
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