tools: avoid accidentally using files from gnulib

The AM_CPPFLAGS setting includes the gnulib headers, which
means we can get some replacement functions defined. Since
virt-login-shell and the NSS module intentionally don't link
to gnulib, these replacement functions causes link failures.

This was seen cross-compiling on Debian for example:

virt-login-shell.o: In function `main':
/builds/libvirt/libvirt/build/tools/../../tools/virt-login-shell.c:81: undefined reference to `rpl_strerror'
/builds/libvirt/libvirt/build/tools/../../tools/virt-login-shell.c:66: undefined reference to `rpl_strerror'
/builds/libvirt/libvirt/build/tools/../../tools/virt-login-shell.c:75: undefined reference to `rpl_strerror'

The only way to avoid these replacement gnulib headers is
to drop the -Ignulib/lib flags. We do still want to use
gnulib for configmake.h and intprops.h, but those can be
included via their full path.

We must also stop using internal.h, since that expects
-Ignulib/lib to be on the include path in order to resolve
the verify.h header.

Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

cfg.mk

@@ -1346,3 +1346,6 @@ exclude_file_name_regexp--sc_prohibit_cross_inclusion = \
 
 exclude_file_name_regexp--sc_prohibit_dirent_d_type = \
   ^(src/util/vircgroup.c)$
+
+exclude_file_name_regexp--sc_prohibit_strcmp = \
+  ^(tools/nss/libvirt_nss.*\.c)

tools/Makefile.am

@@ -23,6 +23,12 @@ AM_CPPFLAGS = \
 	-I$(top_srcdir) \
 	$(NULL)
 
+# We do not want to accidentally include stuff from gnulib
+# or the main src/ dir or public API dir. Specific files can
+# still be included via their path relative to the root if
+# needed
+STANDALONE_CPPFLAGS = -I$(top_srcdir)
+
 WARN_CFLAGS += $(STRICT_FRAME_LIMIT_CFLAGS)
 
 AM_CFLAGS = \
@@ -199,6 +205,8 @@ virt_host_validate_CFLAGS = \
 virt_login_shell_SOURCES = \
 		virt-login-shell.c
 
+virt_login_shell_CPPFLAGS = $(STANDALONE_CPPFLAGS)
+
 virt_login_shell_helper_SOURCES = \
 		virt-login-shell-helper.c
 
@@ -486,6 +494,7 @@ noinst_LTLIBRARIES += nss/libnss_libvirt_impl.la
 nss_libnss_libvirt_impl_la_SOURCES = \
 	$(LIBVIRT_NSS_SOURCES)
 
+nss_libnss_libvirt_impl_la_CPPFLAGS = $(STANDALONE_CPPFLAGS)
 nss_libnss_libvirt_impl_la_CFLAGS = \
 	-DLIBVIRT_NSS \
 	$(YAJL_CFLAGS) \
@@ -516,6 +525,7 @@ nss_libnss_libvirt_guest_impl_la_SOURCES = \
 	nss/libvirt_nss_macs.c \
 	$(NULL)
 
+nss_libnss_libvirt_guest_impl_la_CPPFLAGS = $(STANDALONE_CPPFLAGS)
 nss_libnss_libvirt_guest_impl_la_CFLAGS = \
 	-DLIBVIRT_NSS \
 	-DLIBVIRT_NSS_GUEST \

tools/nss/libvirt_nss.c

@@ -32,6 +32,8 @@
 #include <dirent.h>
 #include <arpa/inet.h>
 #include <stdlib.h>
+#include <stdbool.h>
+#include <errno.h>
 #include <string.h>
 #include <time.h>
 
@@ -40,7 +42,12 @@
 # include <nsswitch.h>
 #endif
 
-#include "configmake.h"
+/*
+ * This gnulib files is used for its macros only,
+ * so doesn't introduce a link time dep, which we
+ * must avoid
+ */
+#include "gnulib/lib/configmake.h"
 
 #include "libvirt_nss_leases.h"
 
@@ -131,7 +138,7 @@ findLease(const char *name,
         char *path;
         size_t dlen = strlen(entry->d_name);
 
-        if (dlen >= 7 && STREQ(entry->d_name + dlen - 7, ".status")) {
+        if (dlen >= 7 && !strcmp(entry->d_name + dlen - 7, ".status")) {
             char **tmpLease;
             if (asprintf(&path, "%s/%s", leaseDir, entry->d_name) < 0)
                 goto cleanup;
@@ -142,7 +149,7 @@ findLease(const char *name,
             leaseFiles = tmpLease;
             leaseFiles[nleaseFiles++] = path;
 #if defined(LIBVIRT_NSS_GUEST)
-        } else if (dlen >= 5 && STREQ(entry->d_name + dlen - 5, ".macs")) {
+        } else if (dlen >= 5 && !strcmp(entry->d_name + dlen - 5, ".macs")) {
             if (asprintf(&path, "%s/%s", leaseDir, entry->d_name) < 0)
                 goto cleanup;
 

tools/nss/libvirt_nss_leases.c

@@ -23,6 +23,7 @@
 #include <unistd.h>
 #include <string.h>
 #include <stdlib.h>
+#include <stdbool.h>
 #include <fcntl.h>
 
 #include <yajl/yajl_gen.h>
@@ -60,7 +61,7 @@ typedef struct {
 
 
 static int
-appendAddr(const char *name ATTRIBUTE_UNUSED,
+appendAddr(const char *name __attribute__((unused)),
            leaseAddress **tmpAddress,
            size_t *ntmpAddress,
            const char *ipAddr,
@@ -165,7 +166,7 @@ findLeasesParserInteger(void *ctx,
         return 0;
 
     if (parser->state == FIND_LEASES_STATE_ENTRY) {
-        if (STRNEQ(parser->key, "expiry-time"))
+        if (strcmp(parser->key, "expiry-time"))
             return 0;
 
         parser->entry.expiry = val;
@@ -190,13 +191,13 @@ findLeasesParserString(void *ctx,
         return 0;
 
     if (parser->state == FIND_LEASES_STATE_ENTRY) {
-        if (STREQ(parser->key, "ip-address")) {
+        if (!strcmp(parser->key, "ip-address")) {
             if (!(parser->entry.ipaddr = strndup((char *)stringVal, stringLen)))
                 return 0;
-        } else if (STREQ(parser->key, "mac-address")) {
+        } else if (!strcmp(parser->key, "mac-address")) {
             if (!(parser->entry.macaddr = strndup((char *)stringVal, stringLen)))
                 return 0;
-        } else if (STREQ(parser->key, "hostname")) {
+        } else if (!strcmp(parser->key, "hostname")) {
             if (!(parser->entry.hostname = strndup((char *)stringVal, stringLen)))
                 return 0;
         } else {
@@ -264,12 +265,12 @@ findLeasesParserEndMap(void *ctx)
         DEBUG("Check %zu macs", parser->nmacs);
         for (i = 0; i < parser->nmacs && !found; i++) {
             DEBUG("Check mac '%s' vs '%s'", parser->macs[i], NULLSTR(parser->entry.macaddr));
-            if (STREQ_NULLABLE(parser->macs[i], parser->entry.macaddr))
+            if (parser->entry.macaddr && !strcmp(parser->macs[i], parser->entry.macaddr))
                 found = true;
         }
     } else {
         DEBUG("Check name '%s' vs '%s'", parser->name, NULLSTR(parser->entry.hostname));
-        if (STREQ_NULLABLE(parser->name, parser->entry.hostname))
+        if (parser->entry.hostname && !strcmp(parser->name, parser->entry.hostname))
             found = true;
     }
     DEBUG("Found %d", found);

tools/nss/libvirt_nss_leases.h

@@ -20,7 +20,7 @@
 
 #pragma once
 
-#include "internal.h"
+#include <sys/types.h>
 
 typedef struct {
     unsigned char addr[16];

tools/nss/libvirt_nss_macs.c

@@ -67,7 +67,7 @@ findMACsParserString(void *ctx,
         return 0;
 
     if (parser->state == FIND_MACS_STATE_ENTRY) {
-        if (STRNEQ(parser->key, "domain"))
+        if (strcmp(parser->key, "domain"))
             return 0;
 
         free(parser->entry.name);
@@ -75,7 +75,7 @@ findMACsParserString(void *ctx,
             return 0;
     } else if (parser->state == FIND_MACS_STATE_ENTRY_MACS) {
         char **macs;
-        if (STRNEQ(parser->key, "macs"))
+        if (strcmp(parser->key, "macs"))
             return 0;
 
         if (!(macs = realloc(parser->entry.macs,
@@ -142,7 +142,7 @@ findMACsParserEndMap(void *ctx)
     if (parser->state != FIND_MACS_STATE_ENTRY)
         return 0;
 
-    if (STREQ(parser->entry.name, parser->name)) {
+    if (!strcmp(parser->entry.name, parser->name)) {
         char **macs = realloc(*parser->macs,
                               sizeof(char *) * ((*parser->nmacs) + parser->entry.nmacs));
         if (!macs)

tools/nss/libvirt_nss_macs.h

@@ -20,7 +20,7 @@
 
 #pragma once
 
-#include "internal.h"
+#include <sys/types.h>
 
 int
 findMACs(const char *file,

tools/virt-login-shell.c

@@ -28,8 +28,12 @@
 #include <errno.h>
 #include <string.h>
 
-#include "configmake.h"
-#include "intprops.h"
+/*
+ * These gnulib files are used for their macros only,
+ * so don't introduce a link time dep, which we must avoid
+ */
+#include "gnulib/lib/configmake.h"
+#include "gnulib/lib/intprops.h"
 
 int main(int argc, char **argv) {
     char uidstr[INT_BUFSIZE_BOUND(uid_t)];