Hurd compat fixes. Mostly dealing with absent PATH_MAX

Signed-off-by: Jérémie Koenig <jk@jk.fr.eu.org>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

13 files changed, 85 insertions, 61 deletions

diff --git a/coreutils/realpath.c b/coreutils/realpath.c
index 28906ba..90a71ed 100644
--- a/coreutils/realpath.c
+++ b/coreutils/realpath.c
@@ -17,30 +17,20 @@ int realpath_main(int argc UNUSED_PARAM, char **argv)
 {
 	int retval = EXIT_SUCCESS;
 
-#if PATH_MAX > (BUFSIZ+1)
-	RESERVE_CONFIG_BUFFER(resolved_path, PATH_MAX);
-# define resolved_path_MUST_FREE 1
-#else
-#define resolved_path bb_common_bufsiz1
-# define resolved_path_MUST_FREE 0
-#endif
-
 	if (!*++argv) {
 		bb_show_usage();
 	}
 
 	do {
-		if (realpath(*argv, resolved_path) != NULL) {
+		char *resolved_path = xmalloc_realpath(*argv);
+	       	if (resolved_path != NULL) {
 			puts(resolved_path);
+			free(resolved_path);
 		} else {
 			retval = EXIT_FAILURE;
 			bb_simple_perror_msg(*argv);
 		}
 	} while (*++argv);
 
-#if ENABLE_FEATURE_CLEAN_UP && resolved_path_MUST_FREE
-	RELEASE_CONFIG_BUFFER(resolved_path);
-#endif
-
 	fflush_stdout_and_exit(retval);
 }
diff --git a/debianutils/start_stop_daemon.c b/debianutils/start_stop_daemon.c
index dfc72f0..0a08025 100644
--- a/debianutils/start_stop_daemon.c
+++ b/debianutils/start_stop_daemon.c
@@ -89,16 +89,17 @@ enum {
 #define TEST  (option_mask32 & OPT_TEST)
 
 struct globals {
-	struct pid_list *found;
+	struct pid_list *found_procs;
 	char *userspec;
 	char *cmdname;
 	char *execname;
 	char *pidfile;
+	char *execname_cmpbuf;
+	unsigned execname_sizeof;
 	int user_id;
 	smallint signal_nr;
 } FIX_ALIASING;
 #define G (*(struct globals*)&bb_common_bufsiz1)
-#define found             (G.found               )
 #define userspec          (G.userspec            )
 #define cmdname           (G.cmdname             )
 #define execname          (G.execname            )
@@ -118,7 +119,7 @@ struct globals {
 static int pid_is_exec(pid_t pid)
 {
 	struct stat st;
-	char buf[sizeof("/proc//exe") + sizeof(int)*3];
+	char buf[sizeof("/proc/%u/exe") + sizeof(int)*3];
 
 	sprintf(buf, "/proc/%u/exe", (unsigned)pid);
 	if (stat(buf, &st) < 0)
@@ -133,13 +134,13 @@ static int pid_is_exec(pid_t pid)
 static int pid_is_exec(pid_t pid)
 {
 	ssize_t bytes;
-	char buf[PATH_MAX];
+	char buf[sizeof("/proc/%u/cmdline") + sizeof(int)*3];
 
 	sprintf(buf, "/proc/%u/cmdline", (unsigned)pid);
-	bytes = open_read_close(buf, buf, sizeof(buf) - 1);
+	bytes = open_read_close(buf, G.execname_cmpbuf, G.execname_sizeof);
 	if (bytes > 0) {
-		buf[bytes] = '\0';
-		return strcmp(buf, execname) == 0;
+		G.execname_cmpbuf[bytes] = '\0';
+		return strcmp(execname, G.execname_cmpbuf) == 0;
 	}
 	return 0;
 }
@@ -194,9 +195,9 @@ static void check(int pid)
 		return;
 	}
 	p = xmalloc(sizeof(*p));
-	p->next = found;
+	p->next = G.found_procs;
 	p->pid = pid;
-	found = p;
+	G.found_procs = p;
 }
 
 static void do_pidfile(void)
@@ -266,13 +267,13 @@ static int do_stop(void)
 		bb_error_msg_and_die("internal error, please report");
 	}
 
-	if (!found) {
+	if (!G.found_procs) {
 		if (!QUIET)
 			printf("no %s found; none killed\n", what);
 		killed = -1;
 		goto ret;
 	}
-	for (p = found; p; p = p->next) {
+	for (p = G.found_procs; p; p = p->next) {
 		if (TEST || kill(p->pid, signal_nr) == 0) {
 			killed++;
 		} else {
@@ -282,7 +283,7 @@ static int do_stop(void)
 	}
 	if (!QUIET && killed) {
 		printf("stopped %s (pid", what);
-		for (p = found; p; p = p->next)
+		for (p = G.found_procs; p; p = p->next)
 			if (p->pid)
 				printf(" %u", (unsigned)p->pid);
 		puts(")");
@@ -365,6 +366,10 @@ int start_stop_daemon_main(int argc UNUSED_PARAM, char **argv)
 		startas = execname;
 	if (!execname) /* in case -a is given and -x is not */
 		execname = startas;
+	if (execname) {
+		G.execname_sizeof = strlen(execname) + 1;
+		G.execname_cmpbuf = xmalloc(G.execname_sizeof + 1);
+	}
 
 //	IF_FEATURE_START_STOP_DAEMON_FANCY(
 //		if (retry_arg)
@@ -386,9 +391,9 @@ int start_stop_daemon_main(int argc UNUSED_PARAM, char **argv)
 		return (opt & OPT_OKNODO) ? 0 : (i <= 0);
 	}
 
-	if (found) {
+	if (G.found_procs) {
 		if (!QUIET)
-			printf("%s is already running\n%u\n", execname, (unsigned)found->pid);
+			printf("%s is already running\n%u\n", execname, (unsigned)G.found_procs->pid);
 		return !(opt & OPT_OKNODO);
 	}
 
diff --git a/include/libbb.h b/include/libbb.h
index 72d6c7d..794e438 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -339,7 +339,7 @@ void xmove_fd(int, int) FAST_FUNC;
 DIR *xopendir(const char *path) FAST_FUNC;
 DIR *warn_opendir(const char *path) FAST_FUNC;
 
-/* UNUSED: char *xmalloc_realpath(const char *path) FAST_FUNC RETURNS_MALLOC; */
+char *xmalloc_realpath(const char *path) FAST_FUNC RETURNS_MALLOC;
 char *xmalloc_readlink(const char *path) FAST_FUNC RETURNS_MALLOC;
 char *xmalloc_readlink_or_warn(const char *path) FAST_FUNC RETURNS_MALLOC;
 /* !RETURNS_MALLOC: it's a realloc-like function */
diff --git a/libbb/safe_gethostname.c b/libbb/safe_gethostname.c
index 7407fb7..e93254b 100644
--- a/libbb/safe_gethostname.c
+++ b/libbb/safe_gethostname.c
@@ -59,8 +59,12 @@ char* FAST_FUNC safe_gethostname(void)
  */
 char* FAST_FUNC safe_getdomainname(void)
 {
+/* The field domainname of struct utsname is Linux specific. */
+#if defined(__linux__)
 	struct utsname uts;
-
 	uname(&uts);
 	return xstrndup(!uts.domainname[0] ? "?" : uts.domainname, sizeof(uts.domainname));
+#else
+	return xstrdup("?");
+#endif
 }
diff --git a/libbb/xconnect.c b/libbb/xconnect.c
index 97751eb..d8c8d02 100644
--- a/libbb/xconnect.c
+++ b/libbb/xconnect.c
@@ -21,6 +21,8 @@ int FAST_FUNC setsockopt_broadcast(int fd)
 {
 	return setsockopt(fd, SOL_SOCKET, SO_BROADCAST, &const_int_1, sizeof(const_int_1));
 }
+
+#ifdef SO_BINDTODEVICE
 int FAST_FUNC setsockopt_bindtodevice(int fd, const char *iface)
 {
 	int r;
@@ -36,6 +38,14 @@ int FAST_FUNC setsockopt_bindtodevice(int fd, const char *iface)
 		bb_perror_msg("can't bind to interface %s", iface);
 	return r;
 }
+#else
+int FAST_FUNC setsockopt_bindtodevice(int fd UNUSED_PARAM,
+		const char *iface UNUSED_PARAM)
+{
+	bb_error_msg("SO_BINDTODEVICE is not supported on this system");
+	return -1;
+}
+#endif
 
 len_and_sockaddr* FAST_FUNC get_sock_lsa(int fd)
 {
diff --git a/libbb/xreadlink.c b/libbb/xreadlink.c
index 8d232f1..faa0e16 100644
--- a/libbb/xreadlink.c
+++ b/libbb/xreadlink.c
@@ -100,18 +100,16 @@ char* FAST_FUNC xmalloc_readlink_or_warn(const char *path)
 	return buf;
 }
 
-/* UNUSED */
-#if 0
 char* FAST_FUNC xmalloc_realpath(const char *path)
 {
 #if defined(__GLIBC__) && !defined(__UCLIBC__)
 	/* glibc provides a non-standard extension */
+	/* new: POSIX.1-2008 specifies this behavior as well */
 	return realpath(path, NULL);
 #else
 	char buf[PATH_MAX+1];
 
-	/* on error returns NULL (xstrdup(NULL) ==NULL) */
+	/* on error returns NULL (xstrdup(NULL) == NULL) */
 	return xstrdup(realpath(path, buf));
 #endif
 }
-#endif
diff --git a/scripts/basic/docproc.c b/scripts/basic/docproc.c
index dc7a0fc..ef51812 100644
--- a/scripts/basic/docproc.c
+++ b/scripts/basic/docproc.c
@@ -79,7 +79,9 @@ void exec_kernel_doc(char **svec)
 {
 	pid_t pid;
 	int ret;
-	char real_filename[PATH_MAX + 1];
+	char *real_filename;
+	int rflen;
+
 	/* Make sure output generated so far are flushed */
 	fflush(stdout);
 	switch(pid=fork()) {
@@ -87,10 +89,11 @@ void exec_kernel_doc(char **svec)
 			perror("fork");
 			exit(1);
 		case  0:
-			memset(real_filename, 0, sizeof(real_filename));
-			strncat(real_filename, getenv("SRCTREE"), PATH_MAX);
-			strncat(real_filename, KERNELDOCPATH KERNELDOC,
-					PATH_MAX - strlen(real_filename));
+			rflen  = strlen(getenv("SRCTREE"));
+			rflen += strlen(KERNELDOCPATH KERNELDOC);
+			real_filename = alloca(rflen + 1);
+			strcpy(real_filename, getenv("SRCTREE"));
+			strcat(real_filename, KERNELDOCPATH KERNELDOC);
 			execvp(real_filename, svec);
 			fprintf(stderr, "exec ");
 			perror(real_filename);
@@ -166,11 +169,10 @@ void find_export_symbols(char * filename)
 	struct symfile *sym;
 	char line[MAXLINESZ];
 	if (filename_exist(filename) == NULL) {
-		char real_filename[PATH_MAX + 1];
-		memset(real_filename, 0, sizeof(real_filename));
-		strncat(real_filename, getenv("SRCTREE"), PATH_MAX);
-		strncat(real_filename, filename,
-				PATH_MAX - strlen(real_filename));
+		int rflen = strlen(getenv("SRCTREE")) + strlen(filename);
+		char *real_filename = alloca(rflen + 1);
+		strcpy(real_filename, getenv("SRCTREE"));
+		strcat(real_filename, filename);
 		sym = add_new_file(filename);
 		fp = fopen(real_filename, "r");
 		if (fp == NULL)
diff --git a/scripts/basic/fixdep.c b/scripts/basic/fixdep.c
index 6d61044..bbb575c 100644
--- a/scripts/basic/fixdep.c
+++ b/scripts/basic/fixdep.c
@@ -203,7 +203,7 @@ void clear_config(void)
  */
 void use_config(char *m, int slen)
 {
-	char s[PATH_MAX];
+	char *s = alloca(slen+1);
 	char *p;
 
 	if (is_defined_config(m, slen))
@@ -310,7 +310,7 @@ void parse_dep_file(void *map, size_t len)
 	char *m = map;
 	char *end = m + len;
 	char *p;
-	char s[PATH_MAX];
+	char *s = alloca(len);
 
 	p = memchr(m, ':', len);
 	if (!p) {
diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index 9365a12..4f83fbf 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -70,12 +70,13 @@ static char *conf_expand_value(const char *in)
 char *conf_get_default_confname(void)
 {
 	struct stat buf;
-	static char fullname[PATH_MAX+1];
+	static char *fullname = NULL;
 	char *env, *name;
 
 	name = conf_expand_value(conf_defname);
 	env = getenv(SRCTREE);
 	if (env) {
+		fullname = realloc(fullname, strlen(env) + strlen(name) + 2);
 		sprintf(fullname, "%s/%s", env, name);
 		if (!stat(fullname, &buf))
 			return fullname;
diff --git a/scripts/kconfig/mconf.c b/scripts/kconfig/mconf.c
index 647ec09..0c548bf 100644
--- a/scripts/kconfig/mconf.c
+++ b/scripts/kconfig/mconf.c
@@ -258,7 +258,7 @@ search_help[] = N_(
 
 static char buf[4096], *bufptr = buf;
 static char input_buf[4096];
-static char filename[PATH_MAX+1] = ".config";
+static const char filename[] = ".config";
 static char *args[1024], **argptr = args;
 static int indent;
 static struct termios ios_org;
diff --git a/scripts/kconfig/zconf.l b/scripts/kconfig/zconf.l
index d839577..6a58b80 100644
--- a/scripts/kconfig/zconf.l
+++ b/scripts/kconfig/zconf.l
@@ -265,13 +265,14 @@ static void zconf_endhelp(void)
  */
 FILE *zconf_fopen(const char *name)
 {
-	char *env, fullname[PATH_MAX+1];
+	char *env;
 	FILE *f;
 
 	f = fopen(name, "r");
 	if (!f && name[0] != '/') {
 		env = getenv(SRCTREE);
 		if (env) {
+			char *fullname = alloca(strlen(env) + strlen(name) + 2);
 			sprintf(fullname, "%s/%s", env, name);
 			f = fopen(fullname, "r");
 		}
diff --git a/scripts/kconfig/zconf.y b/scripts/kconfig/zconf.y
index 0a7a796..2007a4e 100644
--- a/scripts/kconfig/zconf.y
+++ b/scripts/kconfig/zconf.y
@@ -14,8 +14,6 @@
 #define LKC_DIRECT_LINK
 #include "lkc.h"
 
-#include "zconf.hash.c"
-
 #define printd(mask, fmt...) if (cdebug & (mask)) printf(fmt)
 
 #define PRINTD		0x0001
@@ -99,6 +97,10 @@ static struct menu *current_menu, *current_entry;
 		menu_end_menu();
 } if_entry menu_entry choice_entry
 
+%{
+#include "zconf.hash.c"
+%}
+
 %%
 input: stmt_list;
 
diff --git a/util-linux/umount.c b/util-linux/umount.c
index a4b2bd0..a19f86c 100644
--- a/util-linux/umount.c
+++ b/util-linux/umount.c
@@ -39,6 +39,10 @@
 # define MS_RELATIME    (1 << 21)
 #endif
 #include "libbb.h"
+#ifndef PATH_MAX
+# define PATH_MAX (4*1024)
+#endif
+
 
 #if defined(__dietlibc__)
 /* 16.12.2006, Sampo Kellomaki (sampo@iki.fi)
@@ -69,7 +73,7 @@ int umount_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int umount_main(int argc UNUSED_PARAM, char **argv)
 {
 	int doForce;
-	char *const path = xmalloc(PATH_MAX + 2); /* to save stack */
+	char *const buf = xmalloc(PATH_MAX * 2 + 128); /* to save stack */
 	struct mntent me;
 	FILE *fp;
 	char *fstype = NULL;
@@ -100,7 +104,7 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
 		if (opt & OPT_ALL)
 			bb_error_msg_and_die("can't open '%s'", bb_path_mtab_file);
 	} else {
-		while (getmntent_r(fp, &me, path, PATH_MAX)) {
+		while (getmntent_r(fp, &me, buf, PATH_MAX * 2 + 128)) {
 			/* Match fstype if passed */
 			if (!match_fstype(&me, fstype))
 				continue;
@@ -124,10 +128,11 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
 	for (;;) {
 		int curstat;
 		char *zapit = *argv;
+		char *path;
 
 		// Do we already know what to umount this time through the loop?
 		if (m)
-			safe_strncpy(path, m->dir, PATH_MAX);
+			path = xstrdup(m->dir);
 		// For umount -a, end of mtab means time to exit.
 		else if (opt & OPT_ALL)
 			break;
@@ -136,10 +141,12 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
 			if (!zapit)
 				break;
 			argv++;
-			realpath(zapit, path);
-			for (m = mtl; m; m = m->next)
-				if (!strcmp(path, m->dir) || !strcmp(path, m->device))
-					break;
+			path = xmalloc_realpath(zapit);
+			if (path) {
+				for (m = mtl; m; m = m->next)
+					if (strcmp(path, m->dir) == 0 || strcmp(path, m->device) == 0)
+						break;
+			}
 		}
 		// If we couldn't find this sucker in /etc/mtab, punt by passing our
 		// command line argument straight to the umount syscall.  Otherwise,
@@ -181,9 +188,13 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
 		// Find next matching mtab entry for -a or umount /dev
 		// Note this means that "umount /dev/blah" will unmount all instances
 		// of /dev/blah, not just the most recent.
-		if (m) while ((m = m->next) != NULL)
-			if ((opt & OPT_ALL) || !strcmp(path, m->device))
-				break;
+		if (m) {
+			while ((m = m->next) != NULL)
+				// NB: if m is non-NULL, path is non-NULL as well
+				if ((opt & OPT_ALL) || strcmp(path, m->device) == 0)
+					break;
+		}
+		free(path);
 	}
 
 	// Free mtab list if necessary
@@ -195,7 +206,7 @@ int umount_main(int argc UNUSED_PARAM, char **argv)
 			free(mtl);
 			mtl = m;
 		}
-		free(path);
+		free(buf);
 	}
 
 	return status;