Support both getline and fgetln

Some libc implementations don't have the getline function but instead
have an equivalent fgetln function.

Add code to detect both and use whatever is available.

Signed-off-by: Stéphane Graber <stgraber@ubuntu.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>

diff --git a/configure.ac b/configure.ac
index 564df0ecd54347e2eeee2f419fbaa2a5514b0573..4793573140f2437b4e651b30e2c434cba9796eec 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -216,6 +216,15 @@ AC_CHECK_DECLS([PR_CAPBSET_DROP], [], [], [#include <sys/prctl.h>])
 # Check for optional headers
 AC_CHECK_HEADERS([sys/signalfd.h])
 
+AC_CHECK_FUNCS([getline],
+       AM_CONDITIONAL(HAVE_GETLINE, true)
+       AC_DEFINE(HAVE_GETLINE,1,[Have getline]),
+       AM_CONDITIONAL(HAVE_GETLINE, false))
+AC_CHECK_FUNCS([fgetln],
+       AM_CONDITIONAL(HAVE_FGETLN, true)
+       AC_DEFINE(HAVE_FGETLN,1,[Have fgetln]),
+       AM_CONDITIONAL(HAVE_FGETLN, false))
+
 # Check for some standard binaries
 AC_PROG_GCC_TRADITIONAL
 AC_PROG_SED

diff --git a/src/include/getline.c b/src/include/getline.c
new file mode 100644 (file)
index 0000000..d4117cb
--- /dev/null
+++ b/src/include/getline.c
@@ -0,0 +1,31 @@
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * Emulate glibc getline() via BSD fgetln().
+ * Note that outsize is not changed unless memory is allocated.
+ */
+ssize_t
+getline(char **outbuf, size_t *outsize, FILE *fp)
+{
+    size_t len;
+    char *buf;
+    buf = fgetln(fp, &len);
+
+    if (buf == NULL)
+        return (-1);
+
+    /* Assumes realloc() accepts NULL for ptr (C99) */
+    if (*outbuf == NULL || *outsize < len + 1) {
+        void *tmp = realloc(*outbuf, len + 1);
+        if (tmp == NULL)
+            return (-1);
+        *outbuf = tmp;
+        *outsize = len + 1;
+    }
+    memcpy(*outbuf, buf, len);
+    (*outbuf)[len] = '\0';
+    return (len);
+}

diff --git a/src/include/getline.h b/src/include/getline.h
new file mode 100644 (file)
index 0000000..b030d7a
--- /dev/null
+++ b/src/include/getline.h
@@ -0,0 +1,6 @@
+#ifndef _getline_h
+#define _getline_h
+
+extern ssize_t getline(char **outbuf, size_t *outsize, FILE *fp);
+
+#endif

diff --git a/src/lxc/Makefile.am b/src/lxc/Makefile.am
index bf675f9d0078356cec3878513967e6b25567f342..ef02b6dd1322022758388faf04fe81e0188221fc 100644 (file)
--- a/src/lxc/Makefile.am
+++ b/src/lxc/Makefile.am
@@ -17,6 +17,12 @@ pkginclude_HEADERS = \
                lxccontainer.h \
                lxclock.h
 
+if !HAVE_GETLINE
+if HAVE_FGETLN
+pkginclude_HEADERS += ../include/getline.h
+endif
+endif
+
 sodir=$(libdir)
 # use PROGRAMS to avoid complains from automake
 so_PROGRAMS = liblxc.so
@@ -61,6 +67,12 @@ liblxc_so_SOURCES = \
        lxclock.h lxclock.c \
        lxccontainer.c lxccontainer.h
 
+if !HAVE_GETLINE
+if HAVE_FGETLN
+liblxc_so_SOURCES += ../include/getline.c ../include/getline.h
+endif
+endif
+
 AM_CFLAGS=-I$(top_srcdir)/src \
        -DLXCROOTFSMOUNT=\"$(LXCROOTFSMOUNT)\" \
        -DLXCPATH=\"$(LXCPATH)\" \

diff --git a/src/lxc/attach.c b/src/lxc/attach.c
index ec0e08300e28af9148ad90ae89f53a51393708b8..9b7efbc0b7f4bb798e530af4ef3a60bd6c65a428 100644 (file)
--- a/src/lxc/attach.c
+++ b/src/lxc/attach.c
@@ -31,6 +31,7 @@
 #include <sys/param.h>
 #include <sys/prctl.h>
 #include <sys/mount.h>
+#include <sys/syscall.h>
 #include <linux/unistd.h>
 
 #if !HAVE_DECL_PR_CAPBSET_DROP
@@ -56,6 +57,13 @@ int setns(int fd, int nstype)
 #endif
 }
 
+/* Define getline() if missing from the C library */
+#ifndef HAVE_GETLINE
+#ifdef HAVE_FGETLN
+#include <../include/getline.h>
+#endif
+#endif
+
 struct lxc_proc_context_info *lxc_proc_get_context_info(pid_t pid)
 {
        struct lxc_proc_context_info *info = calloc(1, sizeof(*info));

diff --git a/src/lxc/parse.c b/src/lxc/parse.c
index 10510c9d951ae958853b2efc6ac0f42e7a46be08..b074b047b484ebb6f976f0d345a1d9732e90417e 100644 (file)
--- a/src/lxc/parse.c
+++ b/src/lxc/parse.c
@@ -29,8 +29,16 @@
 #include <dirent.h>
 
 #include "parse.h"
+#include "config.h"
 #include <lxc/log.h>
 
+/* Define getline() if missing from the C library */
+#ifndef HAVE_GETLINE
+#ifdef HAVE_FGETLN
+#include <../include/getline.h>
+#endif
+#endif
+
 lxc_log_define(lxc_parse, lxc);
 
 static int dir_filter(const struct dirent *dirent)