libpkgconf: refactor out the rfc822 message parser so that the cross-personality code can share it

Makefile.am

@@ -137,7 +137,8 @@ libpkgconf_la_SOURCES  =	\
 		libpkgconf/dependency.c		\
 		libpkgconf/queue.c		\
 		libpkgconf/path.c		\
-		libpkgconf/personality.c
+		libpkgconf/personality.c	\
+		libpkgconf/parser.c
 libpkgconf_la_LDFLAGS = -no-undefined -version-info 3:0:0 -export-symbols-regex '^pkgconf_'
 
 dist_man_MANS    = 		\

libpkgconf/CMakeLists.txt

@@ -13,6 +13,7 @@ ADD_LIBRARY(libpkgconf SHARED
     dependency.c
     fileio.c
     fragment.c
+    parser.c
     path.c
     personality.c
     pkg.c

libpkgconf/libpkgconf.h

@@ -248,7 +248,6 @@ PKGCONF_API const pkgconf_cross_personality_t *pkgconf_cross_personality_default
 #define PKGCONF_PKG_ERRF_PACKAGE_CONFLICT	0x4
 #define PKGCONF_PKG_ERRF_DEPGRAPH_BREAK		0x8
 
-/* pkg.c */
 #if defined(__GNUC__) || defined(__INTEL_COMPILER)
 #define PRINTFLIKE(fmtarg, firstvararg) \
         __attribute__((__format__ (__printf__, fmtarg, firstvararg)))
@@ -259,6 +258,13 @@ PKGCONF_API const pkgconf_cross_personality_t *pkgconf_cross_personality_default
 #define DEPRECATED
 #endif /* defined(__INTEL_COMPILER) || defined(__GNUC__) */
 
+/* parser.c */
+typedef void (*pkgconf_parser_operand_func_t)(void *data, const size_t lineno, const char *key, const char *value);
+typedef void (*pkgconf_parser_warn_func_t)(void *data, const char *fmt, ...);
+
+PKGCONF_API void pkgconf_parser_parse(FILE *f, void *data, const pkgconf_parser_operand_func_t *ops, const pkgconf_parser_warn_func_t warnfunc, const char *filename);
+
+/* pkg.c */
 PKGCONF_API bool pkgconf_error(const pkgconf_client_t *client, const char *format, ...) PRINTFLIKE(2, 3);
 PKGCONF_API bool pkgconf_warn(const pkgconf_client_t *client, const char *format, ...) PRINTFLIKE(2, 3);
 PKGCONF_API bool pkgconf_trace(const pkgconf_client_t *client, const char *filename, size_t lineno, const char *funcname, const char *format, ...) PRINTFLIKE(5, 6);

libpkgconf/parser.c

@@ -0,0 +1,95 @@
+/*
+ * parser.c
+ * rfc822 message parser
+ *
+ * Copyright (c) 2018 pkgconf authors (see AUTHORS).
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * This software is provided 'as is' and without any warranty, express or
+ * implied.  In no event shall the authors be liable for any damages arising
+ * from the use of this software.
+ */
+
+#include <libpkgconf/stdinc.h>
+#include <libpkgconf/config.h>
+#include <libpkgconf/libpkgconf.h>
+
+/*
+ * !doc
+ *
+ * .. c:function:: pkgconf_pkg_t *pkgconf_pkg_new_from_file(const pkgconf_client_t *client, const char *filename, FILE *f)
+ *
+ *    Parse a .pc file into a pkgconf_pkg_t object structure.
+ *
+ *    :param pkgconf_client_t* client: The pkgconf client object to use for dependency resolution.
+ *    :param char* filename: The filename of the package file (including full path).
+ *    :param FILE* f: The file object to read from.
+ *    :returns: A ``pkgconf_pkg_t`` object which contains the package data.
+ *    :rtype: pkgconf_pkg_t *
+ */
+void
+pkgconf_parser_parse(FILE *f, void *data, const pkgconf_parser_operand_func_t *ops, const pkgconf_parser_warn_func_t warnfunc, const char *filename)
+{
+	char readbuf[PKGCONF_BUFSIZE];
+	size_t lineno = 0;
+
+	while (pkgconf_fgetline(readbuf, PKGCONF_BUFSIZE, f) != NULL)
+	{
+		char op, *p, *key, *value;
+		bool warned_key_whitespace = false, warned_value_whitespace = false;
+
+		lineno++;
+
+		p = readbuf;
+		while (*p && (isalpha((unsigned int)*p) || isdigit((unsigned int)*p) || *p == '_' || *p == '.'))
+			p++;
+
+		key = readbuf;
+		if (!isalpha((unsigned int)*key) && !isdigit((unsigned int)*p))
+			continue;
+
+		while (*p && isspace((unsigned int)*p))
+		{
+			if (!warned_key_whitespace)
+			{
+				warnfunc(data, "%s:" SIZE_FMT_SPECIFIER ": warning: whitespace encountered while parsing key section\n",
+					filename, lineno);
+				warned_key_whitespace = true;
+			}
+
+			/* set to null to avoid trailing spaces in key */
+			*p = '\0';
+			p++;
+		}
+
+		op = *p;
+		*p = '\0';
+		p++;
+
+		while (*p && isspace((unsigned int)*p))
+			p++;
+
+		value = p;
+		p = value + (strlen(value) - 1);
+		while (*p && isspace((unsigned int) *p) && p > value)
+		{
+			if (!warned_value_whitespace && op == '=')
+			{
+				warnfunc(data, "%s:" SIZE_FMT_SPECIFIER ": warning: trailing whitespace encountered while parsing value section\n",
+					filename, lineno);
+				warned_value_whitespace = true;
+			}
+
+			*p = '\0';
+			p--;
+		}
+
+		if (ops[(unsigned char) op])
+			ops[(unsigned char) op](data, lineno, key, value);
+	}
+
+	fclose(f);
+}

libpkgconf/pkg.c

@@ -236,6 +236,26 @@ static const pkgconf_pkg_validity_check_t pkgconf_pkg_validations[] = {
 	{"Version", offsetof(pkgconf_pkg_t, version)},
 };
 
+static const pkgconf_parser_operand_func_t pkg_parser_funcs[] = {
+	[':'] = (pkgconf_parser_operand_func_t) pkgconf_pkg_parser_keyword_set,
+	['='] = (pkgconf_parser_operand_func_t) pkgconf_pkg_parser_value_set
+};
+
+static void pkg_warn_func(pkgconf_pkg_t *pkg, const char *fmt, ...) PRINTFLIKE(2, 3);
+
+static void
+pkg_warn_func(pkgconf_pkg_t *pkg, const char *fmt, ...)
+{
+	char buf[PKGCONF_ITEM_SIZE];
+	va_list va;
+
+	va_start(va, fmt);
+	vsnprintf(buf, sizeof buf, fmt, va);
+	va_end(va);
+
+	pkgconf_warn(pkg->owner, "%s", buf);
+}
+
 static bool
 pkgconf_pkg_validate(const pkgconf_client_t *client, const pkgconf_pkg_t *pkg)
 {
@@ -273,9 +293,7 @@ pkgconf_pkg_t *
 pkgconf_pkg_new_from_file(pkgconf_client_t *client, const char *filename, FILE *f)
 {
 	pkgconf_pkg_t *pkg;
-	char readbuf[PKGCONF_BUFSIZE];
 	char *idptr;
-	size_t lineno = 0;
 
 	pkg = calloc(sizeof(pkgconf_pkg_t), 1);
 	pkg->owner = client;
@@ -298,73 +316,7 @@ pkgconf_pkg_new_from_file(pkgconf_client_t *client, const char *filename, FILE *
 	if (idptr)
 		*idptr = '\0';
 
-	while (pkgconf_fgetline(readbuf, PKGCONF_BUFSIZE, f) != NULL)
-	{
-		char op, *p, *key, *value;
-		bool warned_key_whitespace = false, warned_value_whitespace = false;
-
-		lineno++;
-
-		PKGCONF_TRACE(client, "%s:" SIZE_FMT_SPECIFIER " > [%s]", filename, lineno, readbuf);
-
-		p = readbuf;
-		while (*p && (isalpha((unsigned int)*p) || isdigit((unsigned int)*p) || *p == '_' || *p == '.'))
-			p++;
-
-		key = readbuf;
-		if (!isalpha((unsigned int)*key) && !isdigit((unsigned int)*p))
-			continue;
-
-		while (*p && isspace((unsigned int)*p))
-		{
-			if (!warned_key_whitespace)
-			{
-				pkgconf_warn(client, "%s:" SIZE_FMT_SPECIFIER ": warning: whitespace encountered while parsing key section\n",
-					pkg->filename, lineno);
-				warned_key_whitespace = true;
-			}
-
-			/* set to null to avoid trailing spaces in key */
-			*p = '\0';
-			p++;
-		}
-
-		op = *p;
-		*p = '\0';
-		p++;
-
-		while (*p && isspace((unsigned int)*p))
-			p++;
-
-		value = p;
-		p = value + (strlen(value) - 1);
-		while (*p && isspace((unsigned int) *p) && p > value)
-		{
-			if (!warned_value_whitespace && op == '=')
-			{
-				pkgconf_warn(client, "%s:" SIZE_FMT_SPECIFIER ": warning: trailing whitespace encountered while parsing value section\n",
-					pkg->filename, lineno);
-				warned_value_whitespace = true;
-			}
-
-			*p = '\0';
-			p--;
-		}
-
-		switch (op)
-		{
-		case ':':
-			pkgconf_pkg_parser_keyword_set(pkg, lineno, key, value);
-			break;
-		case '=':
-			pkgconf_pkg_parser_value_set(pkg, lineno, key, value);
-			break;
-		default:
-			break;
-		}
-	}
-
-	fclose(f);
+	pkgconf_parser_parse(f, pkg, pkg_parser_funcs, (pkgconf_parser_warn_func_t) pkg_warn_func, pkg->filename);
 
 	if (!pkgconf_pkg_validate(client, pkg))
 	{

meson.build

@@ -66,6 +66,7 @@ libpkgconf = shared_library('pkgconf',
   'libpkgconf/dependency.c',
   'libpkgconf/fileio.c',
   'libpkgconf/fragment.c',
+  'libpkgconf/parser.c',
   'libpkgconf/path.c',
   'libpkgconf/personality.c',
   'libpkgconf/pkg.c',