1 files changed, 110 insertions, 73 deletions

diff --git a/libpkgconf/parser.c b/libpkgconf/parser.c
index 3a66b8af2a8d..11f023267388 100644
--- a/libpkgconf/parser.c
+++ b/libpkgconf/parser.c
@@ -2,7 +2,9 @@
  * parser.c
  * rfc822 message parser
  *
- * Copyright (c) 2018 pkgconf authors (see AUTHORS).
+ * SPDX-License-Identifier: pkgconf
+ *
+ * Copyright (c) 2018, 2025 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
@@ -17,97 +19,132 @@
 #include <libpkgconf/stdinc.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)
+static void
+pkgconf_parser_canonicalize_line(pkgconf_buffer_t *buffer)
 {
-	pkgconf_buffer_t readbuf = PKGCONF_BUFFER_INITIALIZER;
-	size_t lineno = 0;
-	bool continue_reading = true;
-
-	while (continue_reading)
-	{
-		char op, *p, *key, *value;
-		bool warned_key_whitespace = false, warned_value_whitespace = false;
-
-		continue_reading = pkgconf_fgetline(&readbuf, f);
-		lineno++;
+	bool escaped = false;
+	char *buf = buffer->base;
+	char *src = buf, *dst = buf;
 
-		p = readbuf.base;
-		if (p == NULL)
-			continue;
-		while (*p && isspace((unsigned char)*p))
-			p++;
-		if (*p && p != readbuf.base)
-		{
-			warnfunc(data, "%s:" SIZE_FMT_SPECIFIER ": warning: whitespace encountered while parsing key section\n",
-				filename, lineno);
-			warned_key_whitespace = true;
-		}
-		key = p;
-		while (*p && (isalpha((unsigned char)*p) || isdigit((unsigned char)*p) || *p == '_' || *p == '.'))
-			p++;
+	if (buf == NULL)
+		return;
 
-		if (!isalpha((unsigned char)*key) &&
-		    !isdigit((unsigned char)*p))
+	for (; *src != '\0'; src++)
+	{
+		if (*src == '\\' && !escaped)
 		{
-			pkgconf_buffer_reset(&readbuf);
+			escaped = true;
 			continue;
 		}
 
-		while (*p && isspace((unsigned char)*p))
+		if (*src == '#' && !escaped)
+			break;
+
+		if (escaped)
 		{
-			if (!warned_key_whitespace)
+			if (*src == '#')
 			{
-				warnfunc(data, "%s:" SIZE_FMT_SPECIFIER ": warning: whitespace encountered while parsing key section\n",
-					filename, lineno);
-				warned_key_whitespace = true;
+				*dst++ = '#';
+				escaped = false;
+				continue;
 			}
 
-			/* set to null to avoid trailing spaces in key */
-			*p = '\0';
-			p++;
+			*dst++ = '\\';
+			escaped = false;
 		}
 
-		op = *p;
-		if (*p != '\0')
+		*dst++ = *src;
+	}
+
+	if (escaped)
+		*dst++ = '\\';
+
+	*dst = '\0';
+	buffer->end = dst;
+}
+
+void
+pkgconf_parser_parse_buffer(void *data, const pkgconf_parser_operand_func_t *ops, const pkgconf_parser_warn_func_t warnfunc, pkgconf_buffer_t *buffer, const char *warnprefix)
+{
+	char op, *p, *key, *value;
+	size_t vallen;
+
+	pkgconf_parser_canonicalize_line(buffer);
+
+	p = buffer->base;
+	if (p == NULL)
+		return;
+	while (*p && isspace((unsigned char)*p))
+		p++;
+	if (*p && p != buffer->base)
+	{
+		warnfunc(data, "%s: warning: whitespace encountered while parsing key section\n",
+			warnprefix);
+	}
+	key = p;
+	while (*p && (isalpha((unsigned char)*p) || isdigit((unsigned char)*p) || *p == '_' || *p == '.'))
+		p++;
+
+	if (!isalpha((unsigned char)*key) && !isdigit((unsigned char)*key))
+		return;
+
+	while (*p && isspace((unsigned char)*p))
+	{
+		warnfunc(data, "%s: warning: whitespace encountered while parsing key section\n",
+			warnprefix);
+
+		/* set to null to avoid trailing spaces in key */
+		*p = '\0';
+		p++;
+	}
+
+	op = *p;
+	if (*p != '\0')
+	{
+		*p = '\0';
+		p++;
+	}
+
+	while (*p && isspace((unsigned char)*p))
+		p++;
+
+	value = p;
+	vallen = strlen(value);
+	if (vallen)
+		p = value + (vallen - 1);
+
+	while (*p && isspace((unsigned char) *p) && p > value)
+	{
+		if (op == '=')
 		{
-			*p = '\0';
-			p++;
+			warnfunc(data, "%s: warning: trailing whitespace encountered while parsing value section\n",
+				warnprefix);
 		}
 
-		while (*p && isspace((unsigned char)*p))
-			p++;
+		*p = '\0';
+		p--;
+	}
 
-		value = p;
-		p = value + (strlen(value) - 1);
-		while (*p && isspace((unsigned char) *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;
-			}
+	if (ops[(unsigned char) op])
+		ops[(unsigned char) op](data, warnprefix, key, value);
+}
 
-			*p = '\0';
-			p--;
-		}
-		if (ops[(unsigned char) op])
-			ops[(unsigned char) op](data, lineno, key, value);
+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)
+{
+	pkgconf_buffer_t readbuf = PKGCONF_BUFFER_INITIALIZER;
+	size_t lineno = 0;
+	bool continue_reading = true;
+
+	while (continue_reading)
+	{
+		char warnprefix[PKGCONF_ITEM_SIZE];
+
+		continue_reading = pkgconf_fgetline(&readbuf, f);
+		lineno++;
 
+		snprintf(warnprefix, sizeof warnprefix, "%s:" SIZE_FMT_SPECIFIER, filename, lineno);
+		pkgconf_parser_parse_buffer(data, ops, warnfunc, &readbuf, warnprefix);
 		pkgconf_buffer_reset(&readbuf);
 	}