From 507d7d73abfb1db0835942a82850c0f0a309040a Mon Sep 17 00:00:00 2001
From: Jonas 'Sortie' Termansen <sortie@maxsi.org>
Date: Mon, 28 Dec 2015 02:04:01 +0100
Subject: [PATCH] Add --manifest option to mkinitrd(8).

---
 mkinitrd/mkinitrd.8   |  5 ++++
 mkinitrd/mkinitrd.cpp | 12 +++++++++
 mkinitrd/rules.cpp    | 60 ++++++++++++++++++++++++++++++++++++++++++-
 mkinitrd/rules.h      |  4 +++
 4 files changed, 80 insertions(+), 1 deletion(-)

diff --git a/mkinitrd/mkinitrd.8 b/mkinitrd/mkinitrd.8
index fc9ffbcd..a49b4950 100644
--- a/mkinitrd/mkinitrd.8
+++ b/mkinitrd/mkinitrd.8
@@ -8,6 +8,7 @@
 .Nm mkinitrd
 .Op Fl \-filter Ns "=" Ns Ar rules-file
 .Op Fl \-format Ns "=" Ns Ar format
+.Op Fl \-manifest Ns "=" Ns Ar manifest-file
 .Fl o Ar destination
 .Ar directory ...
 .Sh DESCRIPTION
@@ -61,6 +62,10 @@ is an alias for the newest format
 will default to a newer format when one is introduced and this allows
 .Nm
 to support old callers during the transitional period.
+.It Fl \-manifest Ns "=" Ns Ar manifest-file
+Include only files and directories during the recursive search whose path
+exactly matches a line in the
+.Ar manifest-file .
 .It Fl o , Fl \-output Ns "=" Ns Ar destination
 Store the produced
 .Xr initrd 7
diff --git a/mkinitrd/mkinitrd.cpp b/mkinitrd/mkinitrd.cpp
index f6e895c9..dc796e27 100644
--- a/mkinitrd/mkinitrd.cpp
+++ b/mkinitrd/mkinitrd.cpp
@@ -658,6 +658,7 @@ int main(int argc, char* argv[])
 {
 	char* arg_filter = NULL;
 	char* arg_format = strdup(DEFAULT_FORMAT);
+	char* arg_manifest = NULL;
 	char* arg_output = NULL;
 
 	const char* argv0 = argv[0];
@@ -711,6 +712,17 @@ int main(int argc, char* argv[])
 			free(arg_filter);
 			arg_filter = NULL;
 		}
+		else if ( GET_OPTION_VARIABLE("--manifest", &arg_manifest) )
+		{
+			FILE* fp = fopen(arg_manifest, "r");
+			if ( !fp )
+				error(1, errno, "%s", arg_manifest);
+			if ( !path_filter.AddManifestFromFile(fp, stderr, arg_manifest) )
+				exit(1);
+			fclose(fp);
+			free(arg_manifest);
+			arg_manifest = NULL;
+		}
 		else if ( GET_OPTION_VARIABLE("--format", &arg_format) ) { }
 		else if ( GET_OPTION_VARIABLE("--output", &arg_output) ) { }
 		else
diff --git a/mkinitrd/rules.cpp b/mkinitrd/rules.cpp
index 3a5919e2..9ef749b4 100644
--- a/mkinitrd/rules.cpp
+++ b/mkinitrd/rules.cpp
@@ -113,6 +113,13 @@ InclusionRules::~InclusionRules()
 	delete[] rules;
 }
 
+static int search_path(const void* a_ptr, const void* b_ptr)
+{
+	const char* key = (const char*) a_ptr;
+	char* path = *(char**) b_ptr;
+	return strcmp(key, path);
+}
+
 bool InclusionRules::IncludesPath(const char* path) const
 {
 	bool determined = false;
@@ -136,7 +143,12 @@ bool InclusionRules::IncludesPath(const char* path) const
 	}
 	if ( !determined )
 		included = default_inclusion;
-	return included;
+	if ( !included )
+		return false;
+	if ( manifest_used &&
+	     !bsearch(path, manifest, manifest_used, sizeof(char*), search_path) )
+		return false;
+	return true;
 }
 
 bool InclusionRules::ChangeRulesAmount(size_t new_length)
@@ -265,3 +277,49 @@ bool InclusionRules::AddRulesFromFile(FILE* fp, FILE* err, const char* fpname)
 	}
 	return true;
 }
+
+int compare_path(const void* a_ptr, const void* b_ptr)
+{
+	const char* a = *(const char* const*) a_ptr;
+	const char* b = *(const char* const*) b_ptr;
+	return strcmp(a, b);
+}
+
+bool InclusionRules::AddManifestFromFile(FILE* fp, FILE* err, const char* fpname)
+{
+	char* line = NULL;
+	size_t line_size = 0;
+	ssize_t line_len;
+	while ( 0 <= (line_len = getline(&line, &line_size, fp)) )
+	{
+		if ( line_len && line[line_len-1] == '\n' )
+			line[line_len-1] = '\0';
+		if ( manifest_used == manifest_length )
+		{
+			size_t new_length = 2 * manifest_length;
+			if ( new_length == 0 )
+				new_length = 64;
+			size_t new_size = new_length * sizeof(char*);
+			char** new_manifest = (char**) realloc(manifest, new_size);
+			if ( !new_manifest )
+			{
+				free(line);
+				error_fp(err, 0, errno, "malloc");
+				return false;
+			}
+			manifest = new_manifest;
+			manifest_length = new_length;
+		}
+		manifest[manifest_used++] = line;
+		line = NULL;
+		line_size = 0;
+	}
+	free(line);
+	if ( ferror(fp) )
+	{
+		error_fp(err, 0, errno, "%s", fpname);
+		return false;
+	}
+	qsort(manifest, manifest_used, sizeof(char*), compare_path);
+	return true;
+}
diff --git a/mkinitrd/rules.h b/mkinitrd/rules.h
index 39812435..0b95e9e5 100644
--- a/mkinitrd/rules.h
+++ b/mkinitrd/rules.h
@@ -52,6 +52,7 @@ public:
 	bool IncludesPath(const char* path) const;
 	bool AddRule(InclusionRule* rule);
 	bool AddRulesFromFile(FILE* fp, FILE* err, const char* fpname);
+	bool AddManifestFromFile(FILE* fp, FILE* err, const char* fpname);
 	bool ChangeRulesAmount(size_t newnum);
 
 public:
@@ -60,6 +61,9 @@ public:
 	size_t num_rules_allocated;
 	bool default_inclusion;
 	bool default_inclusion_determined;
+	char** manifest;
+	size_t manifest_used;
+	size_t manifest_length;
 
 };