Fix typos in comments

Author: Michael Paquier

contrib/pgcrypto/fortuna.c

@@ -304,7 +304,7 @@ get_rand_pool(FState *st)
 	unsigned	rnd;
 
 	/*
-	 * This slightly prefers lower pools - thats OK.
+	 * This slightly prefers lower pools - that is OK.
 	 */
 	rnd = st->key[st->rnd_pos] % NUM_POOLS;
 

src/backend/postmaster/bgwriter.c

@@ -301,7 +301,7 @@ BackgroundWriterMain(void)
 		 * check whether there has been any WAL inserted since the last time
 		 * we've logged a running xacts.
 		 *
-		 * We do this logging in the bgwriter as its the only process thats
+		 * We do this logging in the bgwriter as its the only process that is
 		 * run regularly and returns to its mainloop all the time. E.g.
 		 * Checkpointer, when active, is barely ever in its mainloop and thus
 		 * makes it hard to log regularly.

src/backend/replication/logical/origin.c

@@ -677,7 +677,7 @@ StartupReplicationOrigin(void)
 				 errmsg("could not open file \"%s\": %m",
 						path)));
 
-	/* verify magic, thats written even if nothing was active */
+	/* verify magic, that is written even if nothing was active */
 	readBytes = read(fd, &magic, sizeof(magic));
 	if (readBytes != sizeof(magic))
 		ereport(PANIC,

src/backend/replication/logical/snapbuild.c

@@ -612,7 +612,7 @@ SnapBuildExportSnapshot(SnapBuild *builder)
 void
 SnapBuildClearExportedSnapshot(void)
 {
-	/* nothing exported, thats the usual case */
+	/* nothing exported, that is the usual case */
 	if (!ExportInProgress)
 		return;
 

src/common/pg_lzcompress.c

@@ -153,7 +153,7 @@
  *				  to be coded into a tag.
  *
  *			Finally the match algorithm checks that at least a match
- *			of 3 or more bytes has been found, because thats the smallest
+ *			of 3 or more bytes has been found, because that is the smallest
  *			amount of copy information to code into a tag. If so, a tag
  *			is omitted and all the input bytes covered by that are just
  *			scanned for the history add's, otherwise a literal character