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-rw-r--r--widget/LSBUtils.cpp141
1 files changed, 141 insertions, 0 deletions
diff --git a/widget/LSBUtils.cpp b/widget/LSBUtils.cpp
new file mode 100644
index 0000000000..520d50e5cc
--- /dev/null
+++ b/widget/LSBUtils.cpp
@@ -0,0 +1,141 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "LSBUtils.h"
+
+#include <fstream>
+#include <string>
+#include <string_view>
+#include <unistd.h>
+#include "base/process_util.h"
+#include "mozilla/FileUtils.h"
+#include "mozilla/Result.h"
+#include "mozilla/ResultVariant.h"
+#include "mozilla/ipc/LaunchError.h"
+
+namespace mozilla::widget::lsb {
+
+static const char gLsbReleasePath[] = "/usr/bin/lsb_release";
+static const char gEtcOsReleasePath[] = "/etc/os-release";
+static const char gUsrOsReleasePath[] = "/usr/lib/os-release";
+
+// See https://www.freedesktop.org/software/systemd/man/latest/os-release.html
+bool ExtractAndSetValue(nsACString& aContainer, std::string_view& aValue) {
+ // We assume the value is well formed and doesn't contain escape characters.
+ if (aValue.size() > 1 && (aValue.front() == '"' || aValue.front() == '\'')) {
+ // We assume the quote is properly balanced.
+ aValue = aValue.substr(1, aValue.size() - 2);
+ }
+ aContainer.Assign(aValue.data(), aValue.size());
+ return !aValue.empty();
+}
+
+bool GetOSRelease(nsACString& aDistributor, nsACString& aDescription,
+ nsACString& aRelease, nsACString& aCodename) {
+ std::ifstream stream(gEtcOsReleasePath);
+ if (stream.fail()) {
+ stream.open(gUsrOsReleasePath);
+ if (stream.fail()) {
+ return false;
+ }
+ }
+ bool seen_id = false, seen_pretty_name = false, seen_version_id = false;
+ std::string rawline;
+ nsAutoCString name;
+ while (std::getline(stream, rawline)) {
+ std::string_view line(rawline);
+ size_t pos = line.find('=');
+ if (pos != std::string_view::npos) {
+ auto key = line.substr(0, pos);
+ auto value = line.substr(pos + 1);
+ if (key == "ID") {
+ if (ExtractAndSetValue(aDistributor, value)) {
+ // Capitalize the first letter of the id. This mimics what
+ // lsb_release does on Debian and derivatives. On RH derivatives,
+ // ID tends to be capitalized already.
+ char* c = aDistributor.BeginWriting();
+ if (*c >= 'a' && *c <= 'z') {
+ *c -= ('a' - 'A');
+ }
+ seen_id = true;
+ }
+ } else if (key == "NAME") {
+ ExtractAndSetValue(name, value);
+ } else if (key == "PRETTY_NAME") {
+ if (ExtractAndSetValue(aDescription, value)) seen_pretty_name = true;
+ } else if (key == "VERSION_ID") {
+ if (ExtractAndSetValue(aRelease, value)) seen_version_id = true;
+ } else if (key == "VERSION_CODENAME") {
+ ExtractAndSetValue(aCodename, value);
+ }
+ }
+ }
+ // If NAME is set and only differs from ID in case, use NAME.
+ if (seen_id && !name.IsEmpty() && name.EqualsIgnoreCase(aDistributor)) {
+ aDistributor = name;
+ }
+ // Only consider our work done if we've seen at least ID, PRETTY_NAME and
+ // VERSION_ID.
+ return seen_id && seen_pretty_name && seen_version_id;
+}
+
+bool GetLSBRelease(nsACString& aDistributor, nsACString& aDescription,
+ nsACString& aRelease, nsACString& aCodename) {
+ // Nowadays, /etc/os-release is more likely to be available than
+ // /usr/bin/lsb_release. Relying on the former also avoids forking.
+ if (GetOSRelease(aDistributor, aDescription, aRelease, aCodename)) {
+ return true;
+ }
+
+ if (access(gLsbReleasePath, R_OK) != 0) return false;
+
+ int pipefd[2];
+ if (pipe(pipefd) == -1) {
+ NS_WARNING("pipe() failed!");
+ return false;
+ }
+
+ std::vector<std::string> argv = {gLsbReleasePath, "-idrc"};
+
+ base::LaunchOptions options;
+ options.fds_to_remap.push_back({pipefd[1], STDOUT_FILENO});
+ options.wait = true;
+
+ base::ProcessHandle process;
+ Result<Ok, ipc::LaunchError> err = base::LaunchApp(argv, options, &process);
+ close(pipefd[1]);
+ if (err.isErr()) {
+ NS_WARNING("Failed to spawn lsb_release!");
+ close(pipefd[0]);
+ return false;
+ }
+
+ ScopedCloseFile stream(fdopen(pipefd[0], "r"));
+ if (!stream) {
+ NS_WARNING("Could not wrap fd!");
+ close(pipefd[0]);
+ return false;
+ }
+
+ char dist[256], desc[256], release[256], codename[256];
+ if (fscanf(stream,
+ "Distributor ID:\t%255[^\n]\n"
+ "Description:\t%255[^\n]\n"
+ "Release:\t%255[^\n]\n"
+ "Codename:\t%255[^\n]\n",
+ dist, desc, release, codename) != 4) {
+ NS_WARNING("Failed to parse lsb_release!");
+ return false;
+ }
+
+ aDistributor.Assign(dist);
+ aDescription.Assign(desc);
+ aRelease.Assign(release);
+ aCodename.Assign(codename);
+ return true;
+}
+
+} // namespace mozilla::widget::lsb