diff options
Diffstat (limited to 'packages/gcc/10.4.0/0020-libstdcxx-pure-stdio.patch')
| -rw-r--r-- | packages/gcc/10.4.0/0020-libstdcxx-pure-stdio.patch | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/packages/gcc/10.4.0/0020-libstdcxx-pure-stdio.patch b/packages/gcc/10.4.0/0020-libstdcxx-pure-stdio.patch new file mode 100644 index 00000000..7e3e6e65 --- /dev/null +++ b/packages/gcc/10.4.0/0020-libstdcxx-pure-stdio.patch @@ -0,0 +1,267 @@ +From ce06ad6901b1d24abb90d6baba5fe01c750ffb4e Mon Sep 17 00:00:00 2001 +From: Keith Packard <keithp@keithp.com> +Date: Tue, 15 Dec 2020 17:39:24 +0000 +Subject: [PATCH] libstdc++: Support libc with stdio-only I/O in libstdc++ + +The current libstdc++ basic_file_stdio.cc code assumes a POSIX API +underneath the stdio implementation provided by the host libc. This +means that the host must provide a fairly broad POSIX file API, +including read, write, open, close, lseek and ioctl. + +This patch changes basic_file_stdio.cc to only use basic ANSI-C stdio +functions, allowing it to be used with libc implementations like +picolibc which may not have a POSIX operating system underneath. + +This is enabled by a new --enable-cstdio=stdio_pure configure option. + +Aided-by: Jonathan Wakely <jwakely@redhat.com> +Signed-off-by: Keith Packard <keithp@keithp.com> + +libstdc++-v3/ChangeLog: + + * acinclude.m4 (GLIBCXX_ENABLE_CSTDIO): Allow "stdio_pure" + option and define _GLIBCXX_USE_PURE_STDIO when it is used. Also + add "stdio_posix" option as an alias for "stdio". + * config/io/basic_file_stdio.cc [_GLIBCXX_USE_PURE_STDIO]: Only + use defined stdio entry points for all I/O operations, without + direct calls to underlying POSIX functions. + * config.h.in: Regenerate. + * configure: Regenerate. +--- + libstdc++-v3/acinclude.m4 | 20 ++++++++---- + libstdc++-v3/config.h.in | 3 + + libstdc++-v3/config/io/basic_file_stdio.cc | 46 +++++++++++++++++++++++++---- + libstdc++-v3/configure | 17 +++++++--- + 4 files changed, 69 insertions(+), 17 deletions(-) + +--- a/libstdc++-v3/acinclude.m4 ++++ b/libstdc++-v3/acinclude.m4 +@@ -2797,24 +2797,30 @@ + + + dnl +-dnl Check for which I/O library to use: stdio, or something specific. ++dnl Check for which I/O library to use: stdio and POSIX, or pure stdio. + dnl +-dnl Default is stdio. ++dnl Default is stdio_posix. + dnl + AC_DEFUN([GLIBCXX_ENABLE_CSTDIO], [ + AC_MSG_CHECKING([for underlying I/O to use]) + GLIBCXX_ENABLE(cstdio,stdio,[[[=PACKAGE]]], +- [use target-specific I/O package], [permit stdio]) ++ [use target-specific I/O package], [permit stdio|stdio_posix|stdio_pure]) + +- # Now that libio has been removed, you can have any color you want as long +- # as it's black. This is one big no-op until other packages are added, but +- # showing the framework never hurts. ++ # The only available I/O model is based on stdio, via basic_file_stdio. ++ # The default "stdio" is actually "stdio + POSIX" because it uses fdopen(3) ++ # to get a file descriptor and then uses read(3) and write(3) with it. ++ # The "stdio_pure" model doesn't use fdopen and only uses FILE* for I/O. + case ${enable_cstdio} in +- stdio) ++ stdio*) + CSTDIO_H=config/io/c_io_stdio.h + BASIC_FILE_H=config/io/basic_file_stdio.h + BASIC_FILE_CC=config/io/basic_file_stdio.cc + AC_MSG_RESULT(stdio) ++ ++ if test "x$enable_cstdio" = "xstdio_pure" ; then ++ AC_DEFINE(_GLIBCXX_USE_STDIO_PURE, 1, ++ [Define to restrict std::__basic_file<> to stdio APIs.]) ++ fi + ;; + esac + +--- a/libstdc++-v3/config.h.in ++++ b/libstdc++-v3/config.h.in +@@ -974,6 +974,9 @@ + /* Define if sendfile is available in <sys/sendfile.h>. */ + #undef _GLIBCXX_USE_SENDFILE + ++/* Define to restrict std::__basic_file<> to stdio APIs. */ ++#undef _GLIBCXX_USE_STDIO_PURE ++ + /* Define if struct stat has timespec members. */ + #undef _GLIBCXX_USE_ST_MTIM + +--- a/libstdc++-v3/config/io/basic_file_stdio.cc ++++ b/libstdc++-v3/config/io/basic_file_stdio.cc +@@ -111,13 +111,21 @@ + + // Wrapper handling partial write. + static std::streamsize ++#ifdef _GLIBCXX_USE_STDIO_PURE ++ xwrite(FILE *__file, const char* __s, std::streamsize __n) ++#else + xwrite(int __fd, const char* __s, std::streamsize __n) ++#endif + { + std::streamsize __nleft = __n; + + for (;;) + { ++#ifdef _GLIBCXX_USE_STDIO_PURE ++ const std::streamsize __ret = fwrite(__file, 1, __nleft, __file); ++#else + const std::streamsize __ret = write(__fd, __s, __nleft); ++#endif + if (__ret == -1L && errno == EINTR) + continue; + if (__ret == -1L) +@@ -133,7 +141,7 @@ + return __n - __nleft; + } + +-#ifdef _GLIBCXX_HAVE_WRITEV ++#if defined(_GLIBCXX_HAVE_WRITEV) && !defined(_GLIBCXX_USE_STDIO_PURE) + // Wrapper handling partial writev. + static std::streamsize + xwritev(int __fd, const char* __s1, std::streamsize __n1, +@@ -286,9 +294,11 @@ + __basic_file<char>::is_open() const throw () + { return _M_cfile != 0; } + ++#ifndef _GLIBCCXX_USE_STDIO_PURE + int + __basic_file<char>::fd() throw () + { return fileno(_M_cfile); } ++#endif + + __c_file* + __basic_file<char>::file() throw () +@@ -315,29 +325,47 @@ + { + streamsize __ret; + do ++#ifdef _GLIBCXX_USE_STDIO_PURE ++ __ret = fread(__s, 1, __n, this->file()); ++#else + __ret = read(this->fd(), __s, __n); ++#endif + while (__ret == -1L && errno == EINTR); + return __ret; + } + + streamsize + __basic_file<char>::xsputn(const char* __s, streamsize __n) +- { return xwrite(this->fd(), __s, __n); } ++ { ++#ifdef _GLIBCXX_USE_STDIO_PURE ++ return xwrite(this->file(), __s, __n); ++#else ++ return xwrite(this->fd(), __s, __n); ++#endif ++ } + + streamsize + __basic_file<char>::xsputn_2(const char* __s1, streamsize __n1, + const char* __s2, streamsize __n2) + { + streamsize __ret = 0; +-#ifdef _GLIBCXX_HAVE_WRITEV ++#if defined(_GLIBCXX_HAVE_WRITEV) && !defined(_GLIBCXX_USE_STDIO_PURE) + __ret = xwritev(this->fd(), __s1, __n1, __s2, __n2); + #else + if (__n1) ++#ifdef _GLIBCXX_USE_STDIO_PURE ++ __ret = xwrite(this->file(), __s1, __n1); ++#else + __ret = xwrite(this->fd(), __s1, __n1); ++#endif + + if (__ret == __n1) ++#ifdef _GLIBCXX_USE_STDIO_PURE ++ __ret += xwrite(this->file(), __s2, __n2); ++#else + __ret += xwrite(this->fd(), __s2, __n2); + #endif ++#endif + return __ret; + } + +@@ -350,8 +378,12 @@ + if (__off > numeric_limits<off_t>::max() + || __off < numeric_limits<off_t>::min()) + return -1L; ++#ifdef _GLIBCXX_USE_STDIO_PURE ++ return fseek(this->file(), __off, __way); ++#else + return lseek(this->fd(), __off, __way); + #endif ++#endif + } + + int +@@ -361,7 +393,7 @@ + streamsize + __basic_file<char>::showmanyc() + { +-#ifndef _GLIBCXX_NO_IOCTL ++#if !defined(_GLIBCXX_NO_IOCTL) && !defined(_GLIBCXX_USE_STDIO_PURE) + #ifdef FIONREAD + // Pipes and sockets. + int __num = 0; +@@ -371,7 +403,7 @@ + #endif + #endif + +-#ifdef _GLIBCXX_HAVE_POLL ++#if defined(_GLIBCXX_HAVE_POLL) && !defined(_GLIBCXX_USE_STDIO_PURE) + // Cheap test. + struct pollfd __pfd[1]; + __pfd[0].fd = this->fd(); +@@ -395,9 +427,13 @@ + struct stat __buffer; + const int __err = fstat(this->fd(), &__buffer); + if (!__err && _GLIBCXX_ISREG(__buffer.st_mode)) ++#ifdef _GLIBCXX_USE_STDIO_PURE ++ return __buffer.st_size - fseek(this->file(), 0, ios_base::cur); ++#else + return __buffer.st_size - lseek(this->fd(), 0, ios_base::cur); + #endif + #endif ++#endif + return 0; + } + +--- a/libstdc++-v3/configure ++++ b/libstdc++-v3/configure +@@ -16301,7 +16301,7 @@ + if test "${enable_cstdio+set}" = set; then : + enableval=$enable_cstdio; + case "$enableval" in +- stdio) ;; ++ stdio|stdio_posix|stdio_pure) ;; + *) as_fn_error $? "Unknown argument to enable/disable cstdio" "$LINENO" 5 ;; + esac + +@@ -16311,16 +16311,23 @@ + + + +- # Now that libio has been removed, you can have any color you want as long +- # as it's black. This is one big no-op until other packages are added, but +- # showing the framework never hurts. ++ # The only available I/O model is based on stdio, via basic_file_stdio. ++ # The default "stdio" is actually "stdio + POSIX" because it uses fdopen(3) ++ # to get a file descriptor and then uses read(3) and write(3) with it. ++ # The "stdio_pure" model doesn't use fdopen and only uses FILE* for I/O. + case ${enable_cstdio} in +- stdio) ++ stdio*) + CSTDIO_H=config/io/c_io_stdio.h + BASIC_FILE_H=config/io/basic_file_stdio.h + BASIC_FILE_CC=config/io/basic_file_stdio.cc + { $as_echo "$as_me:${as_lineno-$LINENO}: result: stdio" >&5 + $as_echo "stdio" >&6; } ++ ++ if test "x$enable_cstdio" = "xstdio_pure" ; then ++ ++$as_echo "#define _GLIBCXX_USE_STDIO_PURE 1" >>confdefs.h ++ ++ fi + ;; + esac + |