build-sys: add check for gperf lookup function signature (#5055)

gperf-3.1 generates lookup functions that take a size_t length
parameter instead of unsigned int. Test for this at configure time.

Fixes: https://github.com/systemd/systemd/issues/5039
(cherry picked from commit c9f7b4d356a453a01aa77a6bb74ca7ef49732c08)

configure.ac

@@ -255,6 +255,28 @@ AC_CHECK_SIZEOF(rlim_t,,[
        #include <sys/resource.h>
 ])
 
+GPERF_TEST="$(echo foo,bar | ${GPERF} -L ANSI-C)"
+
+AC_COMPILE_IFELSE(
+        [AC_LANG_PROGRAM([
+                #include <string.h>
+                const char * in_word_set(const char *, size_t);
+                $GPERF_TEST]
+        )],
+        [GPERF_LEN_TYPE=size_t],
+        [AC_COMPILE_IFELSE(
+                [AC_LANG_PROGRAM([
+                        #include <string.h>
+                        const char * in_word_set(const char *, unsigned);
+                        $GPERF_TEST]
+                )],
+                [GPERF_LEN_TYPE=unsigned],
+                [AC_MSG_ERROR([** unable to determine gperf len type])]
+        )]
+)
+
+AC_DEFINE_UNQUOTED([GPERF_LEN_TYPE], [$GPERF_LEN_TYPE], [gperf len type])
+
 # ------------------------------------------------------------------------------
 # we use python to build the man page index
 have_python=no

src/basic/af-list.c

@@ -23,7 +23,7 @@
 #include "af-list.h"
 #include "macro.h"
 
-static const struct af_name* lookup_af(register const char *str, register unsigned int len);
+static const struct af_name* lookup_af(register const char *str, register GPERF_LEN_TYPE len);
 
 #include "af-from-name.h"
 #include "af-to-name.h"

src/basic/arphrd-list.c

@@ -23,7 +23,7 @@
 #include "arphrd-list.h"
 #include "macro.h"
 
-static const struct arphrd_name* lookup_arphrd(register const char *str, register unsigned int len);
+static const struct arphrd_name* lookup_arphrd(register const char *str, register GPERF_LEN_TYPE len);
 
 #include "arphrd-from-name.h"
 #include "arphrd-to-name.h"

src/basic/cap-list.c

@@ -26,7 +26,7 @@
 #include "parse-util.h"
 #include "util.h"
 
-static const struct capability_name* lookup_capability(register const char *str, register unsigned int len);
+static const struct capability_name* lookup_capability(register const char *str, register GPERF_LEN_TYPE len);
 
 #include "cap-from-name.h"
 #include "cap-to-name.h"

src/basic/errno-list.c

@@ -23,7 +23,7 @@
 #include "macro.h"
 
 static const struct errno_name* lookup_errno(register const char *str,
-                                             register unsigned int len);
+                                             register GPERF_LEN_TYPE len);
 
 #include "errno-from-name.h"
 #include "errno-to-name.h"

src/core/load-fragment.h

@@ -113,7 +113,7 @@ int config_parse_fdname(const char *unit, const char *filename, unsigned line, c
 int config_parse_sec_fix_0(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 
 /* gperf prototypes */
-const struct ConfigPerfItem* load_fragment_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* load_fragment_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 extern const char load_fragment_gperf_nulstr[];
 
 typedef enum Disabled {

src/journal/journald-server.h

@@ -163,7 +163,7 @@ void server_dispatch_message(Server *s, struct iovec *iovec, unsigned n, unsigne
 void server_driver_message(Server *s, sd_id128_t message_id, const char *format, ...) _printf_(3,0) _sentinel_;
 
 /* gperf lookup function */
-const struct ConfigPerfItem* journald_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* journald_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 int config_parse_storage(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 

src/login/logind.h

@@ -182,7 +182,7 @@ int manager_unit_is_active(Manager *manager, const char *unit);
 int manager_job_is_active(Manager *manager, const char *path);
 
 /* gperf lookup function */
-const struct ConfigPerfItem* logind_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* logind_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 int manager_set_lid_switch_ignore(Manager *m, usec_t until);
 

src/network/networkd-conf.h

@@ -23,7 +23,7 @@
 
 int manager_parse_config_file(Manager *m);
 
-const struct ConfigPerfItem* networkd_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* networkd_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 int config_parse_duid_type(
                 const char *unit,

src/network/networkd-netdev.h

@@ -174,7 +174,7 @@ NetDevKind netdev_kind_from_string(const char *d) _pure_;
 int config_parse_netdev_kind(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 
 /* gperf */
-const struct ConfigPerfItem* network_netdev_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* network_netdev_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 /* Macros which append INTERFACE= to the message */
 

src/network/networkd-network.h

@@ -230,7 +230,7 @@ int config_parse_lldp_mode(const char *unit, const char *filename, unsigned line
 /* Legacy IPv4LL support */
 int config_parse_ipv4ll(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 
-const struct ConfigPerfItem* network_network_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* network_network_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 extern const sd_bus_vtable network_vtable[];
 

src/nspawn/nspawn-settings.h

@@ -103,7 +103,7 @@ bool settings_private_network(Settings *s);
 
 DEFINE_TRIVIAL_CLEANUP_FUNC(Settings*, settings_free);
 
-const struct ConfigPerfItem* nspawn_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* nspawn_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 int config_parse_capability(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_id128(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

src/resolve/dns-type.c

@@ -29,7 +29,7 @@ typedef const struct {
 } dns_type;
 
 static const struct dns_type_name *
-lookup_dns_type (register const char *str, register unsigned int len);
+lookup_dns_type (register const char *str, register GPERF_LEN_TYPE len);
 
 #include "dns_type-from-name.h"
 #include "dns_type-to-name.h"

src/resolve/resolved-conf.h

@@ -29,7 +29,7 @@ int manager_parse_search_domains_and_warn(Manager *m, const char *string);
 int manager_add_dns_server_by_string(Manager *m, DnsServerType type, const char *word);
 int manager_parse_dns_server_string_and_warn(Manager *m, DnsServerType type, const char *string);
 
-const struct ConfigPerfItem* resolved_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* resolved_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 int config_parse_dns_servers(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_search_domains(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

src/test/test-af-list.c

@@ -24,7 +24,7 @@
 #include "string-util.h"
 #include "util.h"
 
-static const struct af_name* lookup_af(register const char *str, register unsigned int len);
+static const struct af_name* lookup_af(register const char *str, register GPERF_LEN_TYPE len);
 
 #include "af-from-name.h"
 #include "af-list.h"

src/test/test-arphrd-list.c

@@ -24,7 +24,7 @@
 #include "string-util.h"
 #include "util.h"
 
-static const struct arphrd_name* lookup_arphrd(register const char *str, register unsigned int len);
+static const struct arphrd_name* lookup_arphrd(register const char *str, register GPERF_LEN_TYPE len);
 
 #include "arphrd-from-name.h"
 #include "arphrd-list.h"

src/timesync/timesyncd-conf.h

@@ -22,7 +22,7 @@
 #include "conf-parser.h"
 #include "timesyncd-manager.h"
 
-const struct ConfigPerfItem* timesyncd_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* timesyncd_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 int manager_parse_server_string(Manager *m, ServerType type, const char *string);
 

src/udev/net/link-config.h

@@ -92,7 +92,7 @@ const char *mac_policy_to_string(MACPolicy p) _const_;
 MACPolicy mac_policy_from_string(const char *p) _pure_;
 
 /* gperf lookup function */
-const struct ConfigPerfItem* link_config_gperf_lookup(const char *key, unsigned length);
+const struct ConfigPerfItem* link_config_gperf_lookup(const char *key, GPERF_LEN_TYPE length);
 
 int config_parse_mac_policy(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
 int config_parse_name_policy(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);

src/udev/udev-builtin-keyboard.c

@@ -29,7 +29,7 @@
 #include "string-util.h"
 #include "udev.h"
 
-static const struct key *keyboard_lookup_key(const char *str, unsigned len);
+static const struct key *keyboard_lookup_key(const char *str, GPERF_LEN_TYPE len);
 #include "keyboard-keys-from-name.h"
 
 static int install_force_release(struct udev_device *dev, const unsigned *release, unsigned release_count) {