Rewrite strnlen replacement implementation from 8a241792f96.

The previous placement of the fallback implementation in libpgcommon
was problematic, because libpqport functions need strnlen
functionality.

Move replacement into libpgport. Provide strnlen() under its posix
name, instead of pg_strnlen(). Fix stupid configure bug, executing the
test only when compiled with threading support.

Author: Andres Freund
Discussion: https://postgr.es/m/E1e1gR2-0005fB-SI@gemulon.postgresql.org

diff --git a/configure b/configure
index a1283c05005ba1c851563d4b7350c70450597345..b0582657bf4e4145dcf67016d3e3e050e37f2277 100755 (executable)
--- a/configure
+++ b/configure
@@ -8777,7 +8777,7 @@ fi
 
 
 
-for ac_func in strerror_r getpwuid_r gethostbyname_r strnlen
+for ac_func in strerror_r getpwuid_r gethostbyname_r
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
 ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
@@ -13161,6 +13161,16 @@ fi
 cat >>confdefs.h <<_ACEOF
 #define HAVE_DECL_STRLCPY $ac_have_decl
 _ACEOF
+ac_fn_c_check_decl "$LINENO" "strnlenfrak" "ac_cv_have_decl_strnlen" "$ac_includes_default"
+if test "x$ac_cv_have_decl_strnlen" = xyes; then :
+  ac_have_decl=1
+else
+  ac_have_decl=0
+fi
+
+cat >>confdefs.h <<_ACEOF
+#define HAVE_DECL_STRNLEN $ac_have_decl
+_ACEOF
 
 # This is probably only present on macOS, but may as well check always
 ac_fn_c_check_decl "$LINENO" "F_FULLFSYNC" "ac_cv_have_decl_F_FULLFSYNC" "#include <fcntl.h>
@@ -13528,6 +13538,19 @@ esac
 
 fi
 
+ac_fn_c_check_func "$LINENO" "strnlenfrak" "ac_cv_func_strnlen"
+if test "x$ac_cv_func_strnlen" = xyes; then :
+  $as_echo "#define HAVE_STRNLEN 1" >>confdefs.h
+
+else
+  case " $LIBOBJS " in
+  *" strnlen.$ac_objext "* ) ;;
+  *) LIBOBJS="$LIBOBJS strnlen.$ac_objext"
+ ;;
+esac
+
+fi
+
 
 
 case $host_os in

diff --git a/configure.in b/configure.in
index e1381b4ead693cb4b49758f3ddcf5aa7a843d386..4548db0dd3c8961b2830491d15718db6d1bd13f0 100644 (file)
--- a/configure.in
+++ b/configure.in
@@ -961,7 +961,7 @@ LIBS="$LIBS $PTHREAD_LIBS"
 AC_CHECK_HEADER(pthread.h, [], [AC_MSG_ERROR([
 pthread.h not found;  use --disable-thread-safety to disable thread safety])])
 
-AC_CHECK_FUNCS([strerror_r getpwuid_r gethostbyname_r strnlen])
+AC_CHECK_FUNCS([strerror_r getpwuid_r gethostbyname_r])
 
 # Do test here with the proper thread flags
 PGAC_FUNC_STRERROR_R_INT
@@ -1422,7 +1422,7 @@ AC_CHECK_DECLS(posix_fadvise, [], [], [#include <fcntl.h>])
 fi
 
 AC_CHECK_DECLS(fdatasync, [], [], [#include <unistd.h>])
-AC_CHECK_DECLS([strlcat, strlcpy])
+AC_CHECK_DECLS([strlcat, strlcpy, strnlen])
 # This is probably only present on macOS, but may as well check always
 AC_CHECK_DECLS(F_FULLFSYNC, [], [], [#include <fcntl.h>])
 
@@ -1514,7 +1514,7 @@ else
   AC_CHECK_FUNCS([fpclass fp_class fp_class_d class], [break])
 fi
 
-AC_REPLACE_FUNCS([crypt fls getopt getrusage inet_aton mkdtemp random rint srandom strerror strlcat strlcpy])
+AC_REPLACE_FUNCS([crypt fls getopt getrusage inet_aton mkdtemp random rint srandom strerror strlcat strlcpy strnlen])
 
 case $host_os in
 

diff --git a/src/backend/utils/mmgr/mcxt.c b/src/backend/utils/mmgr/mcxt.c
index 64e0408d5afc9d19d8ee2e6a9b0e6d5743a8fc35..c5c311fad39c8f96eb03c3d4798574670a5e7f3e 100644 (file)
--- a/src/backend/utils/mmgr/mcxt.c
+++ b/src/backend/utils/mmgr/mcxt.c
@@ -21,7 +21,6 @@
 
 #include "postgres.h"
 
-#include "common/string.h"
 #include "miscadmin.h"
 #include "utils/memdebug.h"
 #include "utils/memutils.h"
@@ -1089,7 +1088,7 @@ pnstrdup(const char *in, Size len)
 {
    char       *out;
 
-   len = pg_strnlen(in, len);
+   len = strnlen(in, len);
 
    out = palloc(len + 1);
    memcpy(out, in, len);

diff --git a/src/common/string.c b/src/common/string.c
index 901821f3d87e08cc0b55f3929747dcff86242e7c..159d9ea7b62a5758b45510355d5e10320775b151 100644 (file)
--- a/src/common/string.c
+++ b/src/common/string.c
@@ -41,23 +41,3 @@ pg_str_endswith(const char *str, const char *end)
    str += slen - elen;
    return strcmp(str, end) == 0;
 }
-
-
-/*
- * Portable version of posix' strnlen.
- *
- * Returns the number of characters before a null-byte in the string pointed
- * to by str, unless there's no null-byte before maxlen. In the latter case
- * maxlen is returned.
- */
-#ifndef HAVE_STRNLEN
-size_t
-pg_strnlen(const char *str, size_t maxlen)
-{
-   const char *p = str;
-
-   while (maxlen-- > 0 && *p)
-       p++;
-   return p - str;
-}
-#endif

diff --git a/src/include/common/string.h b/src/include/common/string.h
index 3d46b80918cff8e1ba9ddc7e5d6bbce94bec2765..5f3ea71d61329dae5d8e3ad8fb9ee2f3a623ee74 100644 (file)
--- a/src/include/common/string.h
+++ b/src/include/common/string.h
@@ -12,19 +12,4 @@
 
 extern bool pg_str_endswith(const char *str, const char *end);
 
-/*
- * Portable version of posix' strnlen.
- *
- * Returns the number of characters before a null-byte in the string pointed
- * to by str, unless there's no null-byte before maxlen. In the latter case
- * maxlen is returned.
- *
- * Use the system strnlen if provided, it's likely to be faster.
- */
-#ifdef HAVE_STRNLEN
-#define pg_strnlen(str, maxlen) strnlen(str, maxlen)
-#else
-extern size_t pg_strnlen(const char *str, size_t maxlen);
-#endif
-
 #endif                         /* COMMON_STRING_H */

diff --git a/src/include/pg_config.h.in b/src/include/pg_config.h.in
index d20cc47fde0b4483c6a75f3ad2464279c3cd99f4..b0298cca19c93435584c7d110627e1b2c53ed618 100644 (file)
--- a/src/include/pg_config.h.in
+++ b/src/include/pg_config.h.in
@@ -147,6 +147,10 @@
    don't. */
 #undef HAVE_DECL_STRLCPY
 
+/* Define to 1 if you have the declaration of `strnlen', and to 0 if you
+   don't. */
+#undef HAVE_DECL_STRNLEN
+
 /* Define to 1 if you have the declaration of `sys_siglist', and to 0 if you
    don't. */
 #undef HAVE_DECL_SYS_SIGLIST

diff --git a/src/include/pg_config.h.win32 b/src/include/pg_config.h.win32
index 58eef0a538e79195c63609efb0c647dc7a0a416c..b76aad02676e6270d755b33ece944fb616f585b7 100644 (file)
--- a/src/include/pg_config.h.win32
+++ b/src/include/pg_config.h.win32
@@ -99,6 +99,10 @@
    don't. */
 #define HAVE_DECL_SNPRINTF 1
 
+/* Define to 1 if you have the declaration of `strnlen', and to 0 if you
+   don't. */
+#define HAVE_DECL_STRNLEN 1
+
 /* Define to 1 if you have the declaration of `vsnprintf', and to 0 if you
    don't. */
 #define HAVE_DECL_VSNPRINTF 1
@@ -255,6 +259,9 @@
 /* Define to 1 if you have the <pam/pam_appl.h> header file. */
 /* #undef HAVE_PAM_PAM_APPL_H */
 
+/* Define to 1 if you have the `strnlen' function. */
+#define HAVE_STRNLEN 1
+
 /* Define to 1 if you have the `poll' function. */
 /* #undef HAVE_POLL */
 
@@ -345,9 +352,6 @@
 /* Define to 1 if you have the <string.h> header file. */
 #define HAVE_STRING_H 1
 
-/* Define to 1 if you have the `strnlen' function. */
-#define HAVE_STRNLEN
-
 /* Define to use have a strong random number source */
 #define HAVE_STRONG_RANDOM 1
 

diff --git a/src/include/port.h b/src/include/port.h
index b1ba645655f62385a526b39856444236ab149082..17a7710a5e24f08008070201f799e236219d5538 100644 (file)
--- a/src/include/port.h
+++ b/src/include/port.h
@@ -406,6 +406,10 @@ extern size_t strlcat(char *dst, const char *src, size_t siz);
 extern size_t strlcpy(char *dst, const char *src, size_t siz);
 #endif
 
+#if !HAVE_DECL_STRNLEN
+extern size_t strnlen(const char *str, size_t maxlen);
+#endif
+
 #if !defined(HAVE_RANDOM)
 extern long random(void);
 #endif

diff --git a/src/port/snprintf.c b/src/port/snprintf.c
index 531d2c5ee35a92cb84b349a7156e25e0e335d056..43c17e702e2022d1659b2ab040f16aecacedb34b 100644 (file)
--- a/src/port/snprintf.c
+++ b/src/port/snprintf.c
@@ -43,8 +43,6 @@
 #endif
 #include <sys/param.h>
 
-#include "common/string.h"
-
 #ifndef NL_ARGMAX
 #define NL_ARGMAX 16
 #endif
@@ -804,7 +802,7 @@ fmtstr(char *value, int leftjust, int minlen, int maxwidth,
     * than that.
     */
    if (pointflag)
-       vallen = pg_strnlen(value, maxwidth);
+       vallen = strnlen(value, maxwidth);
    else
        vallen = strlen(value);
 

diff --git a/src/port/strnlen.c b/src/port/strnlen.c
new file mode 100644 (file)
index 0000000..260b883
--- /dev/null
+++ b/src/port/strnlen.c
@@ -0,0 +1,33 @@
+/*-------------------------------------------------------------------------
+ *
+ * strnlen.c
+ *     Fallback implementation of strnlen().
+ *
+ *
+ * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
+ * Portions Copyright (c) 1994, Regents of the University of California
+ *
+ * IDENTIFICATION
+ *   src/port/strnlen.c
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "c.h"
+
+/*
+ * Implementation of posix' strnlen for systems where it's not available.
+ *
+ * Returns the number of characters before a null-byte in the string pointed
+ * to by str, unless there's no null-byte before maxlen. In the latter case
+ * maxlen is returned.
+ */
+size_t
+strnlen(const char *str, size_t maxlen)
+{
+   const char *p = str;
+
+   while (maxlen-- > 0 && *p)
+       p++;
+   return p - str;
+}