Remove the unused signal blocking code.

According to cl/README.signal, so far, no signal can unintentionally
interrupt a database write without stopping the process and leaving
a file to recover.  Let's keep the never enabled signal blocking code
in the commit history and see what feedback we get.

From [email protected]

Closes #30

Author: bentley

common/exf.c

@@ -841,7 +841,6 @@ file_write(
 		return (1);
 
 	/* Open the file. */
-	SIGBLOCK;
 	if ((fd = open(name, oflags,
 	    S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH)) < 0) {
 		if (errno == EACCES && LF_ISSET(FS_FORCE)) {
@@ -873,11 +872,9 @@ file_write(
 			errno = EACCES;
 		}
 		msgq_str(sp, M_SYSERR, name, "%s");
-		SIGUNBLOCK;
 		return (1);
 	}
 success_open:
-	SIGUNBLOCK;
 
 	/* Try and get a lock. */
 	if (!noname && file_lock(sp, NULL, fd, 0) == LOCK_UNAVAIL)

common/gs.h

@@ -196,21 +196,3 @@ struct _gs {
 					/* Print usage message. */
 	void	(*scr_usage)(void);
 };
-
-/*
- * XXX
- * Block signals if there are asynchronous events.  Used to keep DB system calls
- * from being interrupted and not restarted, as that will result in consistency
- * problems.  This should be handled by DB.
- */
-#ifdef BLOCK_SIGNALS
-#include <signal.h>
-extern sigset_t	__sigblockset;
-#define	SIGBLOCK \
-	(void)sigprocmask(SIG_BLOCK, &__sigblockset, NULL)
-#define	SIGUNBLOCK \
-	(void)sigprocmask(SIG_UNBLOCK, &__sigblockset, NULL);
-#else
-#define	SIGBLOCK
-#define	SIGUNBLOCK
-#endif

common/line.c

@@ -238,13 +238,11 @@ db_delete(
 	/* Update file. */
 	key.data = &lno;
 	key.size = sizeof(lno);
-	SIGBLOCK;
 	if (ep->db->del(ep->db, &key, 0) == 1) {
 		msgq(sp, M_SYSERR,
 		    "003|unable to delete line %lu", (u_long)lno);
 		return (1);
 	}
-	SIGUNBLOCK;
 
 	/* Flush the cache, update line count, before screen update. */
 	if (lno <= ep->c_lno)
@@ -297,13 +295,11 @@ db_append(
 	key.size = sizeof(lno);
 	data.data = fp;
 	data.size = flen;
-	SIGBLOCK;
 	if (ep->db->put(ep->db, &key, &data, R_IAFTER) == -1) {
 		msgq(sp, M_SYSERR,
 		    "004|unable to append to line %lu", (u_long)lno);
 		return (1);
 	}
-	SIGUNBLOCK;
 
 	/* Flush the cache, update line count, before screen update. */
 	if (lno < ep->c_lno)
@@ -375,13 +371,11 @@ db_insert(
 	key.size = sizeof(lno);
 	data.data = fp;
 	data.size = flen;
-	SIGBLOCK;
 	if (ep->db->put(ep->db, &key, &data, R_IBEFORE) == -1) {
 		msgq(sp, M_SYSERR,
 		    "005|unable to insert at line %lu", (u_long)lno);
 		return (1);
 	}
-	SIGUNBLOCK;
 
 	/* Flush the cache, update line count, before screen update. */
 	if (lno >= ep->c_lno)
@@ -446,13 +440,11 @@ db_set(
 	key.size = sizeof(lno);
 	data.data = fp;
 	data.size = flen;
-	SIGBLOCK;
 	if (ep->db->put(ep->db, &key, &data, 0) == -1) {
 		msgq(sp, M_SYSERR,
 		    "006|unable to store line %lu", (u_long)lno);
 		return (1);
 	}
-	SIGUNBLOCK;
 
 	/* Flush the cache, before logging or screen update. */
 	if (lno == ep->c_lno)

common/recover.c

@@ -252,15 +252,12 @@ rcv_sync(
 
 	/* Sync the file if it's been modified. */
 	if (F_ISSET(ep, F_MODIFIED)) {
-		SIGBLOCK;
 		if (ep->db->sync(ep->db, R_RECNOSYNC)) {
 			F_CLR(ep, F_RCV_ON | F_RCV_NORM);
 			msgq_str(sp, M_SYSERR,
 			    ep->rcv_path, "060|File backup failed: %s");
-			SIGUNBLOCK;
 			return (1);
 		}
-		SIGUNBLOCK;
 
 		/* REQUEST: don't remove backing file on exit. */
 		if (LF_ISSET(RCV_PRESERVE))