sbase

commit f7f69125cf296bfd50a483c976f0991ec6e9ffe1
parent f8d39b2329be259e46efd019091e6061de5fbe4b
Author: Roberto E. Vargas Caballero <k0ga@shike2.net>
Date:   Wed, 31 Dec 2025 15:31:21 +0100

make: Synchronize with scc

Scc fixed a race condition hapenning while forking and execing the command
and receiving a signal that could keep make waiting forever. Signals
are correctly masked now to avoid this problems.

Diffstat:
M
make/main.c
 | 
1
+
M
make/make.h
 | 
55
++++++++++++++++++++++++++++---------------------------
M
make/posix.c
 | 
35
+++++++++++++++++++++++++++++------
M
make/rules.c
 | 
9
+++++----

4 files changed, 63 insertions(+), 37 deletions(-)
diff --git a/make/main.c b/make/main.c
@@ -90,6 +90,7 @@ estrdup(char *s)
 void
 sighandler(int signo)
 {
+	killchild();
 	stop = signo;
 }
 
diff --git a/make/make.h b/make/make.h
@@ -43,35 +43,36 @@ struct target {
 	struct target *next;
 };
 
-extern void *emalloc(size_t);
-extern void *erealloc(void *, size_t);
-extern char *estrdup(char *);
-
-extern void dumprules(void);
-extern void dumpmacros(void);
-
-extern char *expandstring(char *, Target *, struct loc *);
-extern void addtarget(char *, int);
-extern void inject(char *);
-extern int build(char *);
-extern int hash(char *);
-extern int parse(char *);
-extern void debug(char *, ...);
-extern void error(char *, ...);
-extern void warning(char *, ...);
-extern void adddep(char *, char *);
-extern void addrule(char *, struct action *, int);
-extern void freeloc(struct loc *);
-
-extern char *getmacro(char *);
-extern void setmacro(char *, char *, int, int);
+void *emalloc(size_t);
+void *erealloc(void *, size_t);
+char *estrdup(char *);
+
+void dumprules(void);
+void dumpmacros(void);
+
+char *expandstring(char *, Target *, struct loc *);
+void addtarget(char *, int);
+void inject(char *);
+int build(char *);
+int hash(char *);
+int parse(char *);
+void debug(char *, ...);
+void error(char *, ...);
+void warning(char *, ...);
+void adddep(char *, char *);
+void addrule(char *, struct action *, int);
+void freeloc(struct loc *);
+
+char *getmacro(char *);
+void setmacro(char *, char *, int, int);
 
 /* system depdendant */
-extern time_t stamp(char *);
-extern int launch(char *, int);
-extern int putenv(char *);
-extern void exportvar(char *, char *);
-extern int is_dir(char *);
+void killchild(void);
+time_t stamp(char *);
+int launch(char *, int);
+int putenv(char *);
+void exportvar(char *, char *);
+int is_dir(char *);
 
 /* main.c */
 extern int kflag, dflag, nflag, iflag, sflag;
diff --git a/make/posix.c b/make/posix.c
@@ -12,6 +12,17 @@
 
 #include "make.h"
 
+
+static volatile pid_t pid;
+
+void
+killchild(void)
+{
+	if (pid != 0)
+		kill(pid, SIGTERM);
+	pid = 0;
+}
+
 int
 is_dir(char *fname)
 {
@@ -49,14 +60,13 @@ int
 launch(char *cmd, int ignore)
 {
 	int st;
-	pid_t pid;
+	sigset_t new, old;
 	char *name, *shell;
 	char *args[] = {NULL, "-ec" , cmd, NULL};
 	static int initsignals;
 	extern char **environ;
 	extern void sighandler(int);
 
-
 	if (!initsignals) {
 		struct sigaction act = {
 			.sa_handler = sighandler
@@ -70,10 +80,25 @@ launch(char *cmd, int ignore)
 		initsignals = 1;
 	}
 
+	sigfillset(&new);
+	sigprocmask(SIG_BLOCK, &new, &old);
+	if (stop)
+		goto unblock;
+
 	switch (pid = fork()) {
 	case -1:
+		perror("make");
+	unblock:
+		sigprocmask(SIG_SETMASK, &old, NULL);
 		return -1;
 	case 0:
+		signal(SIGINT, SIG_DFL);
+		signal(SIGHUP, SIG_DFL);
+		signal(SIGTERM, SIG_DFL);
+		signal(SIGQUIT, SIG_DFL);
+
+		sigprocmask(SIG_SETMASK, &old, NULL);
+
 		shell = getmacro("SHELL");
 
 		if (ignore)
@@ -86,10 +111,8 @@ launch(char *cmd, int ignore)
 		execve(shell, args, environ);
 		_exit(127);
 	default:
-		if (wait(&st) < 0) {
-			kill(pid, SIGTERM);
-			wait(&st);
-		}
+		sigprocmask(SIG_SETMASK, &old, NULL);
+		wait(&st);
 
 		return st;
 	}
diff --git a/make/rules.c b/make/rules.c
@@ -62,10 +62,11 @@ lookup(char *name)
 static void
 cleanup(Target *tp)
 {
-	int precious;
+	int sig, precious;
 	Target *p, **q;
 
-	printf("make: signal %d arrived\n", stop);
+	sig = stop;
+	printf("make: signal %d arrived\n", sig);
 
 	precious = 0;
 	p = lookup(".PRECIOUS");
@@ -81,8 +82,8 @@ cleanup(Target *tp)
 		remove(tp->name);
 	}
 
-	signal(stop, SIG_DFL);
-	raise(stop);
+	signal(sig, SIG_DFL);
+	raise(sig);
 }
 
 static int