Rename backup_compression.{c,h} to compression.{c,h}

Compression option handling (level, algorithm or even workers) can be
used across several parts of the system and not only base backups.
Structures, objects and routines are renamed in consequence, to remove
the concept of base backups from this part of the code making this
change straight-forward.

pg_receivewal, that has gained support for LZ4 since babbbb5, will make
use of this infrastructure for its set of compression options, bringing
more consistency with pg_basebackup.  This cleanup needs to be done
before releasing a beta of 15.  pg_dump is a potential future target, as
well, and adding more compression options to it may happen in 16~.

Author: Michael Paquier
Reviewed-by: Robert Haas, Georgios Kokolatos
Discussion: https://postgr.es/m/YlPQGNAAa04raObK@paquier.xyz

2 files changed, 34 insertions, 34 deletions

diff --git a/src/common/Makefile b/src/common/Makefile
index f627349835c..e9af7346c9c 100644
--- a/src/common/Makefile
+++ b/src/common/Makefile
@@ -47,9 +47,9 @@ LIBS += $(PTHREAD_LIBS)
 
 OBJS_COMMON = \
 	archive.o \
-	backup_compression.o \
 	base64.o \
 	checksum_helper.o \
+	compression.o \
 	config_info.o \
 	controldata_utils.o \
 	d2s.o \
diff --git a/src/common/backup_compression.c b/src/common/compression.c
index 867f2f2eb5e..632fae61442 100644
--- a/src/common/backup_compression.c
+++ b/src/common/compression.c
@@ -1,8 +1,8 @@
 /*-------------------------------------------------------------------------
  *
- * backup_compression.c
+ * compression.c
  *
- * Shared code for backup compression methods and specifications.
+ * Shared code for compression methods and specifications.
  *
  * A compression specification specifies the parameters that should be used
  * when performing compression with a specific algorithm. The simplest
@@ -12,12 +12,12 @@
  * Otherwise, a compression specification is a comma-separated list of items,
  * each having the form keyword or keyword=value.
  *
- * Currently, the only supported keyword is "level".
+ * Currently, the only supported keywords are "level" and "workers".
  *
  * Portions Copyright (c) 1996-2022, PostgreSQL Global Development Group
  *
  * IDENTIFICATION
- *		  src/common/backup_compression.c
+ *		  src/common/compression.c
  *-------------------------------------------------------------------------
  */
 
@@ -27,26 +27,26 @@
 #include "postgres_fe.h"
 #endif
 
-#include "common/backup_compression.h"
+#include "common/compression.h"
 
 static int	expect_integer_value(char *keyword, char *value,
-								 bc_specification *result);
+								 pg_compress_specification *result);
 
 /*
  * Look up a compression algorithm by name. Returns true and sets *algorithm
  * if the name is recognized. Otherwise returns false.
  */
 bool
-parse_bc_algorithm(char *name, bc_algorithm *algorithm)
+parse_compress_algorithm(char *name, pg_compress_algorithm *algorithm)
 {
 	if (strcmp(name, "none") == 0)
-		*algorithm = BACKUP_COMPRESSION_NONE;
+		*algorithm = PG_COMPRESSION_NONE;
 	else if (strcmp(name, "gzip") == 0)
-		*algorithm = BACKUP_COMPRESSION_GZIP;
+		*algorithm = PG_COMPRESSION_GZIP;
 	else if (strcmp(name, "lz4") == 0)
-		*algorithm = BACKUP_COMPRESSION_LZ4;
+		*algorithm = PG_COMPRESSION_LZ4;
 	else if (strcmp(name, "zstd") == 0)
-		*algorithm = BACKUP_COMPRESSION_ZSTD;
+		*algorithm = PG_COMPRESSION_ZSTD;
 	else
 		return false;
 	return true;
@@ -57,17 +57,17 @@ parse_bc_algorithm(char *name, bc_algorithm *algorithm)
  * algorithm.
  */
 const char *
-get_bc_algorithm_name(bc_algorithm algorithm)
+get_compress_algorithm_name(pg_compress_algorithm algorithm)
 {
 	switch (algorithm)
 	{
-		case BACKUP_COMPRESSION_NONE:
+		case PG_COMPRESSION_NONE:
 			return "none";
-		case BACKUP_COMPRESSION_GZIP:
+		case PG_COMPRESSION_GZIP:
 			return "gzip";
-		case BACKUP_COMPRESSION_LZ4:
+		case PG_COMPRESSION_LZ4:
 			return "lz4";
-		case BACKUP_COMPRESSION_ZSTD:
+		case PG_COMPRESSION_ZSTD:
 			return "zstd";
 			/* no default, to provoke compiler warnings if values are added */
 	}
@@ -88,12 +88,12 @@ get_bc_algorithm_name(bc_algorithm algorithm)
  * Note, however, even if there's no parse error, the string might not make
  * sense: e.g. for gzip, level=12 is not sensible, but it does parse OK.
  *
- * Use validate_bc_specification() to find out whether a compression
+ * Use validate_compress_specification() to find out whether a compression
  * specification is semantically sensible.
  */
 void
-parse_bc_specification(bc_algorithm algorithm, char *specification,
-					   bc_specification *result)
+parse_compress_specification(pg_compress_algorithm algorithm, char *specification,
+					   pg_compress_specification *result)
 {
 	int			bare_level;
 	char	   *bare_level_endp;
@@ -113,7 +113,7 @@ parse_bc_specification(bc_algorithm algorithm, char *specification,
 	if (specification != bare_level_endp && *bare_level_endp == '\0')
 	{
 		result->level = bare_level;
-		result->options |= BACKUP_COMPRESSION_OPTION_LEVEL;
+		result->options |= PG_COMPRESSION_OPTION_LEVEL;
 		return;
 	}
 
@@ -175,12 +175,12 @@ parse_bc_specification(bc_algorithm algorithm, char *specification,
 		if (strcmp(keyword, "level") == 0)
 		{
 			result->level = expect_integer_value(keyword, value, result);
-			result->options |= BACKUP_COMPRESSION_OPTION_LEVEL;
+			result->options |= PG_COMPRESSION_OPTION_LEVEL;
 		}
 		else if (strcmp(keyword, "workers") == 0)
 		{
 			result->workers = expect_integer_value(keyword, value, result);
-			result->options |= BACKUP_COMPRESSION_OPTION_WORKERS;
+			result->options |= PG_COMPRESSION_OPTION_WORKERS;
 		}
 		else
 			result->parse_error =
@@ -215,7 +215,7 @@ parse_bc_specification(bc_algorithm algorithm, char *specification,
  * and return -1.
  */
 static int
-expect_integer_value(char *keyword, char *value, bc_specification *result)
+expect_integer_value(char *keyword, char *value, pg_compress_specification *result)
 {
 	int			ivalue;
 	char	   *ivalue_endp;
@@ -247,7 +247,7 @@ expect_integer_value(char *keyword, char *value, bc_specification *result)
  * compression method.
  */
 char *
-validate_bc_specification(bc_specification *spec)
+validate_compress_specification(pg_compress_specification *spec)
 {
 	/* If it didn't even parse OK, it's definitely no good. */
 	if (spec->parse_error != NULL)
@@ -258,24 +258,24 @@ validate_bc_specification(bc_specification *spec)
 	 * a compression level and that the level is within the legal range for
 	 * the algorithm.
 	 */
-	if ((spec->options & BACKUP_COMPRESSION_OPTION_LEVEL) != 0)
+	if ((spec->options & PG_COMPRESSION_OPTION_LEVEL) != 0)
 	{
 		int			min_level = 1;
 		int			max_level;
 
-		if (spec->algorithm == BACKUP_COMPRESSION_GZIP)
+		if (spec->algorithm == PG_COMPRESSION_GZIP)
 			max_level = 9;
-		else if (spec->algorithm == BACKUP_COMPRESSION_LZ4)
+		else if (spec->algorithm == PG_COMPRESSION_LZ4)
 			max_level = 12;
-		else if (spec->algorithm == BACKUP_COMPRESSION_ZSTD)
+		else if (spec->algorithm == PG_COMPRESSION_ZSTD)
 			max_level = 22;
 		else
 			return psprintf(_("compression algorithm \"%s\" does not accept a compression level"),
-							get_bc_algorithm_name(spec->algorithm));
+							get_compress_algorithm_name(spec->algorithm));
 
 		if (spec->level < min_level || spec->level > max_level)
 			return psprintf(_("compression algorithm \"%s\" expects a compression level between %d and %d"),
-							get_bc_algorithm_name(spec->algorithm),
+							get_compress_algorithm_name(spec->algorithm),
 							min_level, max_level);
 	}
 
@@ -283,11 +283,11 @@ validate_bc_specification(bc_specification *spec)
 	 * Of the compression algorithms that we currently support, only zstd
 	 * allows parallel workers.
 	 */
-	if ((spec->options & BACKUP_COMPRESSION_OPTION_WORKERS) != 0 &&
-		(spec->algorithm != BACKUP_COMPRESSION_ZSTD))
+	if ((spec->options & PG_COMPRESSION_OPTION_WORKERS) != 0 &&
+		(spec->algorithm != PG_COMPRESSION_ZSTD))
 	{
 		return psprintf(_("compression algorithm \"%s\" does not accept a worker count"),
-						get_bc_algorithm_name(spec->algorithm));
+						get_compress_algorithm_name(spec->algorithm));
 	}
 
 	return NULL;