improve detection of fdopen() and strerror_r()

3 files changed, 334 insertions, 112 deletions

diff --git a/acinclude.m4 b/acinclude.m4
index a12784285..4d42be49e 100644
--- a/acinclude.m4
+++ b/acinclude.m4
@@ -2620,115 +2620,6 @@ AC_DEFUN([CURL_CHECK_LOCALTIME_R],
         AC_MSG_RESULT(no))])])
 ])
 
-dnl
-dnl This function checks for strerror_r(). If it isn't found at first, it
-dnl retries with _THREAD_SAFE defined, as that is what AIX seems to require
-dnl in order to find this function.
-dnl
-dnl If the function is found, it will then proceed to check how the function
-dnl actually works: glibc-style or POSIX-style.
-dnl
-dnl glibc:
-dnl      char *strerror_r(int errnum, char *buf, size_t n);
-dnl  
-dnl  What this one does is to return the error string (no surprises there),
-dnl  but it doesn't usually copy anything into buf!  The 'buf' and 'n'
-dnl  parameters are only meant as an optional working area, in case strerror_r
-dnl  needs it.  A quick test on a few systems shows that it's generally not
-dnl  touched at all.
-dnl
-dnl POSIX:
-dnl      int strerror_r(int errnum, char *buf, size_t n);
-dnl
-AC_DEFUN([CURL_CHECK_STRERROR_R],
-[
-  AC_CHECK_FUNCS(strerror_r)
-
-  if test "x$ac_cv_func_strerror_r" = "xyes"; then
-
-    AC_MSG_CHECKING(whether strerror_r is declared)
-    AC_EGREP_CPP(strerror_r,[
-#undef _REENTRANT
-#include <string.h>],[
-      AC_MSG_RESULT(yes)],[
-      AC_MSG_RESULT(no)
-      AC_MSG_CHECKING(whether strerror_r with -D_REENTRANT is declared)
-      AC_EGREP_CPP(strerror_r,[
-#undef _REENTRANT
-#define _REENTRANT
-#include <string.h>],[
-        AC_MSG_RESULT(yes)],
-        AC_MSG_RESULT(no)
-        AC_DEFINE(HAVE_NO_STRERROR_R_DECL, 1, [we have no strerror_r() proto])
-       ) dnl with _THREAD_SAFE
-    ]) dnl plain cpp for it
-
-    dnl determine if this strerror_r() is glibc or POSIX
-    AC_MSG_CHECKING([for a glibc strerror_r API])
-    AC_TRY_RUN([
-#include <string.h>
-#include <errno.h>
-int
-main () {
-  char buffer[1024]; /* big enough to play with */
-  char *string =
-    strerror_r(EACCES, buffer, sizeof(buffer));
-    /* this should've returned a string */
-    if(!string || !string[0])
-      return 99;
-    return 0;
-}
-],
-    GLIBC_STRERROR_R="1"
-    AC_DEFINE(HAVE_GLIBC_STRERROR_R, 1, [we have a glibc-style strerror_r()])
-    AC_MSG_RESULT([yes]),
-    AC_MSG_RESULT([no]),
-
-    dnl Use an inferior method of strerror_r detection while cross-compiling
-    AC_EGREP_CPP(yes, [
-#include <features.h>
-#ifdef __GLIBC__
-yes
-#endif
-], 
-      dnl looks like glibc, so assume a glibc-style strerror_r()
-      GLIBC_STRERROR_R="1"
-      AC_DEFINE(HAVE_GLIBC_STRERROR_R, 1, [we have a glibc-style strerror_r()])
-      AC_MSG_RESULT([yes]),
-      AC_MSG_NOTICE([cannot determine strerror_r() style: edit lib/config.h manually!])
-    ) dnl while cross-compiling
-    )
-
-    if test -z "$GLIBC_STRERROR_R"; then
-
-      AC_MSG_CHECKING([for a POSIX strerror_r API])
-      AC_TRY_RUN([
-#include <string.h>
-#include <errno.h>
-int
-main () {
-  char buffer[1024]; /* big enough to play with */
-  int error =
-    strerror_r(EACCES, buffer, sizeof(buffer));
-    /* This should've returned zero, and written an error string in the
-       buffer.*/
-    if(!buffer[0] || error)
-      return 99;
-    return 0;
-}
-],
-      AC_DEFINE(HAVE_POSIX_STRERROR_R, 1, [we have a POSIX-style strerror_r()])
-      AC_MSG_RESULT([yes]),
-      AC_MSG_RESULT([no]) ,
-      dnl cross-compiling!
-      AC_MSG_NOTICE([cannot determine strerror_r() style: edit lib/config.h manually!])
-    )
-
-    fi dnl if not using glibc API
-
-  fi dnl we have a strerror_r
-
-])
 
 AC_DEFUN([CURL_CHECK_INET_NTOA_R],
 [
diff --git a/configure.ac b/configure.ac
index d8d8b0c1f..264d1a43d 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1855,7 +1855,7 @@ else
   CURL_CHECK_LOCALTIME_R()
 
   dnl is there a strerror_r()
-  CURL_CHECK_STRERROR_R()
+  dnl the old strerror_r check was done here
 
   checkfor_gmtime_r="yes"
 fi
@@ -1876,7 +1876,7 @@ if test "x$RECENTAIX" = "xyes"; then
   CURL_CHECK_LOCALTIME_R()
 
   dnl is there a strerror_r()
-  CURL_CHECK_STRERROR_R()
+  dnl the old strerror_r check was done here
 
   checkfor_gmtime_r="yes"
 fi
@@ -2034,10 +2034,12 @@ CURL_CHECK_FUNC_RECVFROM
 CURL_CHECK_FUNC_SEND
 CURL_CHECK_MSG_NOSIGNAL
 
+CURL_CHECK_FUNC_FDOPEN
 CURL_CHECK_FUNC_FTRUNCATE
 CURL_CHECK_FUNC_GMTIME_R
 CURL_CHECK_FUNC_SIGACTION
 CURL_CHECK_FUNC_STRDUP
+CURL_CHECK_FUNC_STRERROR_R
 CURL_CHECK_FUNC_STRTOK_R
 CURL_CHECK_FUNC_STRTOLL
 
diff --git a/m4/curl-functions.m4 b/m4/curl-functions.m4
index 8973e968e..e05e70ee3 100644
--- a/m4/curl-functions.m4
+++ b/m4/curl-functions.m4
@@ -22,7 +22,7 @@
 #***************************************************************************
 
 # File version for 'aclocal' use. Keep it a single number.
-# serial 1
+# serial 5
 
 
 dnl CURL_INCLUDES_SIGNAL
@@ -46,6 +46,27 @@ curl_includes_signal="\
 ])
 
 
+dnl CURL_INCLUDES_STDIO
+dnl -------------------------------------------------
+dnl Set up variable with list of headers that must be
+dnl included when stdio.h is to be included.
+
+AC_DEFUN([CURL_INCLUDES_STDIO], [
+curl_includes_stdio="\
+/* includes start */
+#ifdef HAVE_SYS_TYPES_H
+#  include <sys/types.h>
+#endif
+#ifdef HAVE_STDIO_H
+#  include <stdio.h>
+#endif
+/* includes end */"
+  AC_CHECK_HEADERS(
+    sys/types.h stdio.h,
+    [], [], [$curl_includes_stdio])
+])
+
+
 dnl CURL_INCLUDES_STDLIB
 dnl -------------------------------------------------
 dnl Set up variable with list of headers that must be
@@ -138,6 +159,91 @@ curl_includes_unistd="\
 ])
 
 
+dnl CURL_CHECK_FUNC_FDOPEN
+dnl -------------------------------------------------
+dnl Verify if fdopen is available, prototyped, and
+dnl can be compiled. If all of these are true, and
+dnl usage has not been previously disallowed with
+dnl shell variable curl_disallow_fdopen, then
+dnl HAVE_FDOPEN will be defined.
+
+AC_DEFUN([CURL_CHECK_FUNC_FDOPEN], [
+  AC_REQUIRE([CURL_INCLUDES_STDIO])dnl
+  #
+  tst_links_fdopen="unknown"
+  tst_proto_fdopen="unknown"
+  tst_compi_fdopen="unknown"
+  tst_allow_fdopen="unknown"
+  #
+  AC_MSG_CHECKING([if fdopen can be linked])
+  AC_LINK_IFELSE([
+    AC_LANG_FUNC_LINK_TRY([fdopen])
+  ],[
+    AC_MSG_RESULT([yes])
+    tst_links_fdopen="yes"
+  ],[
+    AC_MSG_RESULT([no])
+    tst_links_fdopen="no"
+  ])
+  #
+  if test "$tst_links_fdopen" = "yes"; then
+    AC_MSG_CHECKING([if fdopen is prototyped])
+    AC_EGREP_CPP([fdopen],[
+      $curl_includes_stdio
+    ],[
+      AC_MSG_RESULT([yes])
+      tst_proto_fdopen="yes"
+    ],[
+      AC_MSG_RESULT([no])
+      tst_proto_fdopen="no"
+    ])
+  fi
+  #
+  if test "$tst_proto_fdopen" = "yes"; then
+    AC_MSG_CHECKING([if fdopen is compilable])
+    AC_COMPILE_IFELSE([
+      AC_LANG_PROGRAM([[
+        $curl_includes_stdio
+      ]],[[
+        if(0 != fdopen(0, 0))
+          return 1;
+      ]])
+    ],[
+      AC_MSG_RESULT([yes])
+      tst_compi_fdopen="yes"
+    ],[
+      AC_MSG_RESULT([no])
+      tst_compi_fdopen="no"
+    ])
+  fi
+  #
+  if test "$tst_compi_fdopen" = "yes"; then
+    AC_MSG_CHECKING([if fdopen usage allowed])
+    if test "x$curl_disallow_fdopen" != "xyes"; then
+      AC_MSG_RESULT([yes])
+      tst_allow_fdopen="yes"
+    else
+      AC_MSG_RESULT([no])
+      tst_allow_fdopen="no"
+    fi
+  fi
+  #
+  AC_MSG_CHECKING([if fdopen might be used])
+  if test "$tst_links_fdopen" = "yes" &&
+     test "$tst_proto_fdopen" = "yes" &&
+     test "$tst_compi_fdopen" = "yes" &&
+     test "$tst_allow_fdopen" = "yes"; then
+    AC_MSG_RESULT([yes])
+    AC_DEFINE_UNQUOTED(HAVE_FDOPEN, 1,
+      [Define to 1 if you have the fdopen function.])
+    ac_cv_func_fdopen="yes"
+  else
+    AC_MSG_RESULT([no])
+    ac_cv_func_fdopen="no"
+  fi
+])
+
+
 dnl CURL_CHECK_FUNC_FTRUNCATE
 dnl -------------------------------------------------
 dnl Verify if ftruncate is available, prototyped, and
@@ -507,6 +613,229 @@ AC_DEFUN([CURL_CHECK_FUNC_STRDUP], [
 ])
 
 
+dnl CURL_CHECK_FUNC_STRERROR_R
+dnl -------------------------------------------------
+dnl Verify if strerror_r is available, prototyped, can be compiled and
+dnl seems to work. If all of these are true, and usage has not been
+dnl previously disallowed with shell variable curl_disallow_strerror_r,
+dnl then HAVE_GLIBC_STRERROR_R or HAVE_POSIX_STRERROR_R will be defined.
+dnl
+dnl glibc-style strerror_r:
+dnl
+dnl      char *strerror_r(int errnum, char *workbuf, size_t bufsize);
+dnl
+dnl  glibc-style strerror_r returns a pointer to the the error string,
+dnl  and might use the provided workbuf as a scratch area if needed. A
+dnl  quick test on a few systems shows that it's usually not used at all.
+dnl
+dnl POSIX-style strerror_r:
+dnl
+dnl      int strerror_r(int errnum, char *resultbuf, size_t bufsize);
+dnl
+dnl  POSIX-style strerror_r returns 0 upon successful completion and the
+dnl  error string in the provided resultbuf.
+dnl
+
+AC_DEFUN([CURL_CHECK_FUNC_STRERROR_R], [
+  AC_REQUIRE([CURL_INCLUDES_STRING])dnl
+  #
+  tst_links_strerror_r="unknown"
+  tst_proto_strerror_r="unknown"
+  tst_compi_strerror_r="unknown"
+  tst_glibc_strerror_r="unknown"
+  tst_posix_strerror_r="unknown"
+  tst_allow_strerror_r="unknown"
+  tst_works_glibc_strerror_r="unknown"
+  tst_works_posix_strerror_r="unknown"
+  #
+  AC_MSG_CHECKING([if strerror_r can be linked])
+  AC_LINK_IFELSE([
+    AC_LANG_FUNC_LINK_TRY([strerror_r])
+  ],[
+    AC_MSG_RESULT([yes])
+    tst_links_strerror_r="yes"
+  ],[
+    AC_MSG_RESULT([no])
+    tst_links_strerror_r="no"
+  ])
+  #
+  if test "$tst_links_strerror_r" = "yes"; then
+    AC_MSG_CHECKING([if strerror_r is prototyped])
+    AC_EGREP_CPP([strerror_r],[
+      $curl_includes_string
+    ],[
+      AC_MSG_RESULT([yes])
+      tst_proto_strerror_r="yes"
+    ],[
+      AC_MSG_RESULT([no])
+      tst_proto_strerror_r="no"
+    ])
+  fi
+  #
+  if test "$tst_proto_strerror_r" = "yes"; then
+    AC_MSG_CHECKING([if strerror_r is compilable])
+    AC_COMPILE_IFELSE([
+      AC_LANG_PROGRAM([[
+        $curl_includes_string
+      ]],[[
+        if(0 != strerror_r(0, 0, 0))
+          return 1;
+      ]])
+    ],[
+      AC_MSG_RESULT([yes])
+      tst_compi_strerror_r="yes"
+    ],[
+      AC_MSG_RESULT([no])
+      tst_compi_strerror_r="no"
+    ])
+  fi
+  #
+  if test "$tst_compi_strerror_r" = "yes"; then
+    AC_MSG_CHECKING([if strerror_r is glibc like])
+    AC_COMPILE_IFELSE([
+      AC_LANG_PROGRAM([[
+        $curl_includes_string
+      ]],[[
+        char *strerror_r(int errnum, char *workbuf, size_t bufsize);
+        if(0 != strerror_r(0, 0, 0))
+          return 1;
+      ]])
+    ],[
+      AC_MSG_RESULT([yes])
+      tst_glibc_strerror_r="yes"
+    ],[
+      AC_MSG_RESULT([no])
+      tst_glibc_strerror_r="no"
+    ])
+  fi
+  #
+  dnl only do runtime verification when not cross-compiling
+  if test "x$cross_compiling" != "xyes" &&
+    test "$tst_glibc_strerror_r" = "yes"; then
+    AC_MSG_CHECKING([if strerror_r seems to work])
+    AC_RUN_IFELSE([
+      AC_LANG_PROGRAM([[
+        $curl_includes_string
+#       include <errno.h>
+      ]],[[
+        char buffer[1024];
+        char *string = 0;
+        buffer[0] = '\0';
+        string = strerror_r(EACCES, buffer, sizeof(buffer));
+        if(!string)
+          exit(1); /* fail */
+        if(!string[0])
+          exit(1); /* fail */
+        else
+          exit(0);
+      ]])
+    ],[
+      AC_MSG_RESULT([yes])
+      tst_works_glibc_strerror_r="yes"
+    ],[
+      AC_MSG_RESULT([no])
+      tst_works_glibc_strerror_r="no"
+    ])
+  fi
+  #
+  if test "$tst_compi_strerror_r" = "yes" &&
+    test "$tst_works_glibc_strerror_r" != "yes"; then
+    AC_MSG_CHECKING([if strerror_r is POSIX like])
+    AC_COMPILE_IFELSE([
+      AC_LANG_PROGRAM([[
+        $curl_includes_string
+      ]],[[
+        int strerror_r(int errnum, char *resultbuf, size_t bufsize);
+        if(0 != strerror_r(0, 0, 0))
+          return 1;
+      ]])
+    ],[
+      AC_MSG_RESULT([yes])
+      tst_posix_strerror_r="yes"
+    ],[
+      AC_MSG_RESULT([no])
+      tst_posix_strerror_r="no"
+    ])
+  fi
+  #
+  dnl only do runtime verification when not cross-compiling
+  if test "x$cross_compiling" != "xyes" &&
+    test "$tst_posix_strerror_r" = "yes"; then
+    AC_MSG_CHECKING([if strerror_r seems to work])
+    AC_RUN_IFELSE([
+      AC_LANG_PROGRAM([[
+        $curl_includes_string
+#       include <errno.h>
+      ]],[[
+        char buffer[1024];
+        int error = 1;
+        buffer[0] = '\0';
+        error = strerror_r(EACCES, buffer, sizeof(buffer));
+        if(error)
+          exit(1); /* fail */
+        if(buffer[0] == '\0')
+          exit(1); /* fail */
+        else
+          exit(0);
+      ]])
+    ],[
+      AC_MSG_RESULT([yes])
+      tst_works_posix_strerror_r="yes"
+    ],[
+      AC_MSG_RESULT([no])
+      tst_works_posix_strerror_r="no"
+    ])
+  fi
+  #
+  if test "$tst_glibc_strerror_r" = "yes" &&
+    test "$tst_works_glibc_strerror_r" != "no" &&
+    test "$tst_posix_strerror_r" != "yes"; then
+    tst_allow_strerror_r="check"
+  fi
+  if test "$tst_posix_strerror_r" = "yes" &&
+    test "$tst_works_posix_strerror_r" != "no" &&
+    test "$tst_glibc_strerror_r" != "yes"; then
+    tst_allow_strerror_r="check"
+  fi
+  if test "$tst_allow_strerror_r" = "check"; then
+    AC_MSG_CHECKING([if strerror_r usage allowed])
+    if test "x$curl_disallow_strerror_r" != "xyes"; then
+      AC_MSG_RESULT([yes])
+      tst_allow_strerror_r="yes"
+    else
+      AC_MSG_RESULT([no])
+      tst_allow_strerror_r="no"
+    fi
+  fi
+  #
+  AC_MSG_CHECKING([if strerror_r might be used])
+  if test "$tst_links_strerror_r" = "yes" &&
+     test "$tst_proto_strerror_r" = "yes" &&
+     test "$tst_compi_strerror_r" = "yes" &&
+     test "$tst_allow_strerror_r" = "yes"; then
+    AC_MSG_RESULT([yes])
+    if test "$tst_glibc_strerror_r" = "yes"; then
+      AC_DEFINE_UNQUOTED(HAVE_GLIBC_STRERROR_R, 1,
+        [Define to 1 if you have a working glibc-style strerror_r function.])
+    fi
+    if test "$tst_posix_strerror_r" = "yes"; then
+      AC_DEFINE_UNQUOTED(HAVE_POSIX_STRERROR_R, 1,
+        [Define to 1 if you have a working POSIX-style strerror_r function.])
+    fi
+    ac_cv_func_strerror_r="yes"
+  else
+    AC_MSG_RESULT([no])
+    ac_cv_func_strerror_r="no"
+  fi
+  #
+  if test "$tst_compi_strerror_r" = "yes" &&
+     test "$tst_allow_strerror_r" = "unknown"; then
+    AC_MSG_NOTICE([cannot determine strerror_r() style: edit lib/config.h manually.])
+  fi
+  #
+])
+
+
 dnl CURL_CHECK_FUNC_STRTOK_R
 dnl -------------------------------------------------
 dnl Verify if strtok_r is available, prototyped, and