MEDIUM: compression: move the zlib-specific stuff from global.h to compression.c

This finishes to clean up the zlib-specific parts. It also unbreaks recent
commit b97c6fb ("CLEANUP: compression: use the build options list to report
the algos") which broke USE_ZLIB due to MAXWBITS not being defined anymore
in haproxy.c.
diff --git a/include/types/global.h b/include/types/global.h
index 9d71eca..0b6d439 100644
--- a/include/types/global.h
+++ b/include/types/global.h
@@ -156,10 +156,6 @@
 		unsigned int ssl_default_dh_param; /* SSL maximum DH parameter size */
 		int ssl_ctx_cache; /* max number of entries in the ssl_ctx cache. */
 #endif
-#ifdef USE_ZLIB
-		int zlibmemlevel;    /* zlib memlevel */
-		int zlibwindowsize;  /* zlib window size */
-#endif
 		int comp_maxlevel;    /* max HTTP compression level */
 		unsigned short idle_timer; /* how long before an empty buffer is considered idle (ms) */
 	} tune;
diff --git a/src/cfgparse.c b/src/cfgparse.c
index 3ed2c22..e9876f8 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -901,54 +901,6 @@
 		}
 		global.tune.max_http_hdr = atol(args[1]);
 	}
-	else if (!strcmp(args[0], "tune.zlib.memlevel")) {
-#ifdef USE_ZLIB
-		if (alertif_too_many_args(1, file, linenum, args, &err_code))
-			goto out;
-		if (*args[1]) {
-			global.tune.zlibmemlevel = atoi(args[1]);
-			if (global.tune.zlibmemlevel < 1 || global.tune.zlibmemlevel > 9) {
-				Alert("parsing [%s:%d] : '%s' expects a numeric value between 1 and 9\n",
-				      file, linenum, args[0]);
-				err_code |= ERR_ALERT | ERR_FATAL;
-				goto out;
-			}
-		} else {
-			Alert("parsing [%s:%d] : '%s' expects a numeric value between 1 and 9\n",
-			      file, linenum, args[0]);
-			err_code |= ERR_ALERT | ERR_FATAL;
-			goto out;
-		}
-#else
-		Alert("parsing [%s:%d] : '%s' is not implemented.\n", file, linenum, args[0]);
-		err_code |= ERR_ALERT | ERR_FATAL;
-		goto out;
-#endif
-	}
-	else if (!strcmp(args[0], "tune.zlib.windowsize")) {
-#ifdef USE_ZLIB
-		if (alertif_too_many_args(1, file, linenum, args, &err_code))
-			goto out;
-		if (*args[1]) {
-			global.tune.zlibwindowsize = atoi(args[1]);
-			if (global.tune.zlibwindowsize < 8 || global.tune.zlibwindowsize > 15) {
-				Alert("parsing [%s:%d] : '%s' expects a numeric value between 8 and 15\n",
-				      file, linenum, args[0]);
-				err_code |= ERR_ALERT | ERR_FATAL;
-				goto out;
-			}
-		} else {
-			Alert("parsing [%s:%d] : '%s' expects a numeric value between 8 and 15\n",
-			      file, linenum, args[0]);
-			err_code |= ERR_ALERT | ERR_FATAL;
-			goto out;
-		}
-#else
-		Alert("parsing [%s:%d] : '%s' is not implemented.\n", file, linenum, args[0]);
-		err_code |= ERR_ALERT | ERR_FATAL;
-		goto out;
-#endif
-	}
 	else if (!strcmp(args[0], "tune.comp.maxlevel")) {
 		if (alertif_too_many_args(1, file, linenum, args, &err_code))
 			goto out;
diff --git a/src/compression.c b/src/compression.c
index 4ce26ec..27ab7f7 100644
--- a/src/compression.c
+++ b/src/compression.c
@@ -26,6 +26,7 @@
 #undef free_func
 #endif /* USE_ZLIB */
 
+#include <common/cfgparse.h>
 #include <common/compat.h>
 #include <common/memory.h>
 
@@ -53,6 +54,9 @@
 
 long zlib_used_memory = 0;
 
+static int global_tune_zlibmemlevel = 8;            /* zlib memlevel */
+static int global_tune_zlibwindowsize = MAX_WBITS;  /* zlib window size */
+
 #endif
 
 unsigned int compress_min_idle = 0;
@@ -479,7 +483,7 @@
 
 	strm = &(*comp_ctx)->strm;
 
-	if (deflateInit2(strm, level, Z_DEFLATED, global.tune.zlibwindowsize + 16, global.tune.zlibmemlevel, Z_DEFAULT_STRATEGY) != Z_OK) {
+	if (deflateInit2(strm, level, Z_DEFLATED, global_tune_zlibwindowsize + 16, global_tune_zlibmemlevel, Z_DEFAULT_STRATEGY) != Z_OK) {
 		deinit_comp_ctx(comp_ctx);
 		return -1;
 	}
@@ -499,7 +503,7 @@
 
 	strm = &(*comp_ctx)->strm;
 
-	if (deflateInit2(strm, level, Z_DEFLATED, -global.tune.zlibwindowsize, global.tune.zlibmemlevel, Z_DEFAULT_STRATEGY) != Z_OK) {
+	if (deflateInit2(strm, level, Z_DEFLATED, -global_tune_zlibwindowsize, global_tune_zlibmemlevel, Z_DEFAULT_STRATEGY) != Z_OK) {
 		deinit_comp_ctx(comp_ctx);
 		return -1;
 	}
@@ -521,7 +525,7 @@
 
 	strm = &(*comp_ctx)->strm;
 
-	if (deflateInit2(strm, level, Z_DEFLATED, global.tune.zlibwindowsize, global.tune.zlibmemlevel, Z_DEFAULT_STRATEGY) != Z_OK) {
+	if (deflateInit2(strm, level, Z_DEFLATED, global_tune_zlibwindowsize, global_tune_zlibmemlevel, Z_DEFAULT_STRATEGY) != Z_OK) {
 		deinit_comp_ctx(comp_ctx);
 		return -1;
 	}
@@ -619,8 +623,61 @@
 	return ret;
 }
 
+/* config parser for global "tune.zlibmemlevel" */
+static int zlib_parse_global_memlevel(char **args, int section_type, struct proxy *curpx,
+                                      struct proxy *defpx, const char *file, int line,
+                                      char **err)
+{
+        if (too_many_args(1, args, err, NULL))
+                return -1;
+
+        if (*(args[1]) == 0) {
+                memprintf(err, "'%s' expects a numeric value between 1 and 9.", args[0]);
+                return -1;
+        }
+
+	global_tune_zlibmemlevel = atoi(args[1]);
+	if (global_tune_zlibmemlevel < 1 || global_tune_zlibmemlevel > 9) {
+                memprintf(err, "'%s' expects a numeric value between 1 and 9.", args[0]);
+                return -1;
+	}
+        return 0;
+}
+
+
+/* config parser for global "tune.zlibwindowsize" */
+static int zlib_parse_global_windowsize(char **args, int section_type, struct proxy *curpx,
+                                        struct proxy *defpx, const char *file, int line,
+                                        char **err)
+{
+        if (too_many_args(1, args, err, NULL))
+                return -1;
+
+        if (*(args[1]) == 0) {
+                memprintf(err, "'%s' expects a numeric value between 8 and 15.", args[0]);
+                return -1;
+        }
+
+	global_tune_zlibwindowsize = atoi(args[1]);
+	if (global_tune_zlibwindowsize < 8 || global_tune_zlibwindowsize > 15) {
+                memprintf(err, "'%s' expects a numeric value between 8 and 15.", args[0]);
+                return -1;
+	}
+        return 0;
+}
+
 #endif /* USE_ZLIB */
 
+
+/* config keyword parsers */
+static struct cfg_kw_list cfg_kws = {ILH, {
+#ifdef USE_ZLIB
+	{ CFG_GLOBAL, "tune.zlib.memlevel",   zlib_parse_global_memlevel },
+	{ CFG_GLOBAL, "tune.zlib.windowsize", zlib_parse_global_windowsize },
+#endif
+	{ 0, NULL, NULL }
+}};
+
 __attribute__((constructor))
 static void __comp_fetch_init(void)
 {
@@ -631,6 +688,9 @@
 	slz_make_crc_table();
 	slz_prepare_dist_table();
 #endif
+#if defined(USE_ZLIB) && defined(DEFAULT_MAXZLIBMEM)
+	global.tune.maxzlibmem = DEFAULT_MAXZLIBMEM * 1024U * 1024U,
+#endif
 #ifdef USE_ZLIB
 	memprintf(&ptr, "Built with zlib version : " ZLIB_VERSION);
 	memprintf(&ptr, "%s\nRunning on zlib version : %s", ptr, zlibVersion());
@@ -646,4 +706,5 @@
 		memprintf(&ptr, "%s none", ptr);
 
 	hap_register_build_opts(ptr, 1);
+	cfg_register_keywords(&cfg_kws);
 }
diff --git a/src/haproxy.c b/src/haproxy.c
index 239db80..ef846fe 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -123,11 +123,7 @@
 	.nbproc = 1,
 	.req_count = 0,
 	.logsrvs = LIST_HEAD_INIT(global.logsrvs),
-#if defined(USE_ZLIB) && defined(DEFAULT_MAXZLIBMEM)
-	.maxzlibmem = DEFAULT_MAXZLIBMEM * 1024U * 1024U,
-#else
 	.maxzlibmem = 0,
-#endif
 	.comp_rate_lim = 0,
 	.ssl_server_verify = SSL_SERVER_VERIFY_REQUIRED,
 	.unix_bind = {
@@ -151,10 +147,6 @@
 #endif
 		.ssl_ctx_cache = DEFAULT_SSL_CTX_CACHE,
 #endif
-#ifdef USE_ZLIB
-		.zlibmemlevel = 8,
-		.zlibwindowsize = MAX_WBITS,
-#endif
 		.comp_maxlevel = 1,
 #ifdef DEFAULT_IDLE_TIMER
 		.idle_timer = DEFAULT_IDLE_TIMER,