Fix typos and some format mistakes in comments

Author: Justin Pryzby
Discussion: https://postgr.es/m/20200612023709.GC14879@telsasoft.com

src/backend/replication/logical/origin.c

@@ -427,7 +427,7 @@ restart:
 
 
 /*
- * Lookup replication origin via it's oid and return the name.
+ * Lookup replication origin via its oid and return the name.
  *
  * The external name is palloc'd in the calling context.
  *

src/backend/replication/logical/relation.c

@@ -576,7 +576,7 @@ logicalrep_partmap_init(void)
  * the attribute map, which can be different for the partition.
  *
  * Note there's no logicalrep_partition_close, because the caller closes the
- * the component relation.
+ * component relation.
  */
 LogicalRepRelMapEntry *
 logicalrep_partition_open(LogicalRepRelMapEntry *root,

src/backend/utils/mmgr/README

@@ -462,7 +462,7 @@ Memory Accounting
 -----------------
 
 One of the basic memory context operations is determining the amount of
-memory used in the context (and it's children). We have multiple places
+memory used in the context (and its children). We have multiple places
 that implement their own ad hoc memory accounting, and this is meant to
 provide a unified approach. Ad hoc accounting solutions work for places
 with tight control over the allocations or when it's easy to determine

src/bin/pg_dump/pg_backup_archiver.c

@@ -209,14 +209,14 @@ dumpOptionsFromRestoreOptions(RestoreOptions *ropt)
 /*
  *	Wrapper functions.
  *
- *	The objective it to make writing new formats and dumpers as simple
+ *	The objective is to make writing new formats and dumpers as simple
  *	as possible, if necessary at the expense of extra function calls etc.
  *
  */
 
 /*
  * The dump worker setup needs lots of knowledge of the internals of pg_dump,
- * so It's defined in pg_dump.c and passed into OpenArchive. The restore worker
+ * so it's defined in pg_dump.c and passed into OpenArchive. The restore worker
  * setup doesn't need to know anything much, so it's defined here.
  */
 static void
@@ -1450,7 +1450,7 @@ SortTocFromFile(Archive *AHX)
 }
 
 /**********************
- * 'Convenience functions that look like standard IO functions
+ * Convenience functions that look like standard IO functions
  * for writing data when in dump mode.
  **********************/
 

src/bin/pg_dump/pg_backup_custom.c

@@ -262,7 +262,6 @@ _ReadExtraToc(ArchiveHandle *AH, TocEntry *te)
  * that includes useful information about the TOC entry.
  *
  * Optional.
- *
  */
 static void
 _PrintExtraToc(ArchiveHandle *AH, TocEntry *te)
@@ -324,7 +323,6 @@ _WriteData(ArchiveHandle *AH, const void *data, size_t dLen)
  * finished.
  *
  * Optional.
- *
  */
 static void
 _EndData(ArchiveHandle *AH, TocEntry *te)
@@ -529,8 +527,8 @@ _LoadBlobs(ArchiveHandle *AH, bool drop)
 /*
  * Skip the BLOBs from the current file position.
  * BLOBS are written sequentially as data blocks (see below).
- * Each BLOB is preceded by it's original OID.
- * A zero OID indicated the end of the BLOBS
+ * Each BLOB is preceded by its original OID.
+ * A zero OID indicates the end of the BLOBS.
  */
 static void
 _skipBlobs(ArchiveHandle *AH)
@@ -548,7 +546,7 @@ _skipBlobs(ArchiveHandle *AH)
 /*
  * Skip data from current file position.
  * Data blocks are formatted as an integer length, followed by data.
- * A zero length denoted the end of the block.
+ * A zero length indicates the end of the block.
 */
 static void
 _skipData(ArchiveHandle *AH)