From: Steinar H. Gunderson <steinar+git@gunderson.no>
Date: Fri, 5 Jan 2024 07:49:04 +0000 (+0100)
Subject: Remove some globals from the bind mount code.
X-Git-Tag: 1.1.21~6
X-Git-Url: https://git.sesse.net/?p=plocate;a=commitdiff_plain;h=3a6c45e1937c698579028b15d4a1c3cc8967172d

Remove some globals from the bind mount code.
---

diff --git a/bind-mount.cpp b/bind-mount.cpp
index 1390a59..899bf3b 100644
--- a/bind-mount.cpp
+++ b/bind-mount.cpp
@@ -38,6 +38,7 @@ any later version.
 #include <sys/stat.h>
 #include <sys/time.h>
 #include <thread>
+#include <optional>
 
 using namespace std;
 
@@ -54,10 +55,10 @@ struct mount {
 };
 
 /* Path to mountinfo */
-static const char *mountinfo_path;
-atomic<bool> mountinfo_updated{ false };
+static atomic<bool> mountinfo_updated{ false };
 
-multimap<pair<int, int>, mount> mount_entries;  // Keyed by device major/minor.
+// Keyed by device major/minor.
+using MountEntries = multimap<pair<int, int>, mount>;
 
 /* Read a line from F.
    Return a string, or empty string on error. */
@@ -168,15 +169,15 @@ static bool read_mount_entry(FILE *f, mount *me)
 
 /* Read mount information from mountinfo_path, update mount_entries and
    num_mount_entries.
-   Return 0 if OK, -1 on error. */
-static int read_mount_entries(void)
+   Return std::nullopt on error. */
+static optional<MountEntries> read_mount_entries(void)
 {
-	FILE *f = fopen(mountinfo_path, "r");
+	FILE *f = fopen(MOUNTINFO_PATH, "r");
 	if (f == nullptr) {
-		return -1;
+		return {};
 	}
 
-	mount_entries.clear();
+	MountEntries mount_entries;
 
 	mount me;
 	while (read_mount_entry(f, &me)) {
@@ -189,7 +190,7 @@ static int read_mount_entries(void)
 		mount_entries.emplace(make_pair(me.dev_major, me.dev_minor), me);
 	}
 	fclose(f);
-	return 0;
+	return mount_entries;
 }
 
 /* Bind mount path list maintenace and top-level interface. */
@@ -209,7 +210,8 @@ static void rebuild_bind_mount_paths(void)
 	if (conf_debug_pruning) {
 		fprintf(stderr, "Rebuilding bind_mount_paths:\n");
 	}
-	if (read_mount_entries() != 0) {
+	optional<MountEntries> mount_entries = read_mount_entries();
+	if (!mount_entries.has_value()) {
 		return;
 	}
 	if (conf_debug_pruning) {
@@ -218,8 +220,8 @@ static void rebuild_bind_mount_paths(void)
 
 	bind_mount_paths.clear();
 
-	for (const auto &[dev_id, me] : mount_entries) {
-		const auto &[first, second] = mount_entries.equal_range(make_pair(me.dev_major, me.dev_minor));
+	for (const auto &[dev_id, me] : *mount_entries) {
+		const auto &[first, second] = mount_entries->equal_range(make_pair(me.dev_major, me.dev_minor));
 		for (auto it = first; it != second; ++it) {
 			const mount &other = it->second;
 			if (other.id == me.id) {
@@ -265,10 +267,9 @@ bool is_bind_mount(const char *path)
 }
 
 /* Initialize state for is_bind_mount(), to read data from MOUNTINFO. */
-void bind_mount_init(const char *mountinfo)
+void bind_mount_init()
 {
-	mountinfo_path = mountinfo;
-	mountinfo_fd = open(mountinfo_path, O_RDONLY);
+	mountinfo_fd = open(MOUNTINFO_PATH, O_RDONLY);
 	if (mountinfo_fd == -1)
 		return;
 	rebuild_bind_mount_paths();
diff --git a/bind-mount.h b/bind-mount.h
index b8c9e5f..b8d76b5 100644
--- a/bind-mount.h
+++ b/bind-mount.h
@@ -30,7 +30,7 @@ any later version.
    (Bind mounts "to self" are ignored.) */
 extern bool is_bind_mount(const char *path);
 
-/* Initialize state for is_bind_mount(), to read data from MOUNTINFO. */
-extern void bind_mount_init(const char *mountinfo);
+/* Initialize state for is_bind_mount(), to read data from MOUNTINFO_PATH. */
+extern void bind_mount_init();
 
 #endif
diff --git a/updatedb.cpp b/updatedb.cpp
index f4cfb02..cf19992 100644
--- a/updatedb.cpp
+++ b/updatedb.cpp
@@ -789,7 +789,7 @@ int main(int argc, char **argv)
 
 	conf_prepare(argc, argv);
 	if (conf_prune_bind_mounts) {
-		bind_mount_init(MOUNTINFO_PATH);
+		bind_mount_init();
 	}
 
 	int fd = open(conf_output.c_str(), O_RDONLY);