web ui Update feature complete.

src/AdminInstallUpdate.cpp

@@ -0,0 +1,157 @@
+// Copyright (c) 2024Robin Davies
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy of
+// this software and associated documentation files (the "Software"), to deal in
+// the Software without restriction, including without limitation the rights to
+// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+// the Software, and to permit persons to whom the Software is furnished to do so,
+// subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+#include "AdminInstallUpdate.hpp"
+#include <fstream>
+#include <stdexcept>
+#include "ss.hpp"
+#include <vector>
+#include <unistd.h>
+#include <fcntl.h>
+#include "Lv2Log.hpp"
+#include <string.h>
+#include <sys/prctl.h>
+#include <sys/wait.h>
+#include <signal.h>
+
+using namespace pipedal;
+namespace fs = std::filesystem;
+
+static fs::path ROOT_INSTALL_DIRECTORY = "/var/pipedal/updates";
+static fs::path INSTALLER_LOG_FILE_PATH = ROOT_INSTALL_DIRECTORY / "install.log";
+
+static fs::path UPDATE_DIRECTORY = ROOT_INSTALL_DIRECTORY / "downloads";
+
+static void removeSignalHandler(int signal)
+{
+    struct sigaction sa;
+    sa.sa_handler = SIG_DFL;
+    sigemptyset(&sa.sa_mask);
+    sa.sa_flags = 0;
+    sigaction(signal, &sa, NULL);
+}
+
+static int exec(const std::string &command)
+{
+    std::string buffer = command;
+
+
+    std::vector<char *> argv;
+    char *p = const_cast<char *>(buffer.c_str());
+    while (*p)
+    {
+        char *start = p;
+        while (*p != ' ' && *p != '\0')
+        {
+            ++p;
+        }
+        argv.push_back(start);
+        while (*p == ' ')
+        {
+            *p++ = '\0';
+        }
+    }
+    argv.push_back(nullptr);
+
+    pid_t pid;
+
+    if ((pid = fork()) == 0)
+    {
+        execv(argv[0], (char *const *)argv.data());
+        write(1,"!\n",2);
+        exit(EXIT_FAILURE);
+    }
+    else
+    {
+        
+        if (pid == -1)
+        {
+            write(1,"*",1);
+            perror("execv");
+            return EXIT_FAILURE;
+        }
+        int returnValue;
+        waitpid(pid, &returnValue, 0);
+
+
+        int exitStatus = WEXITSTATUS(returnValue);
+        return exitStatus;
+    }
+}
+
+void updateLog(const std::string &message)
+{
+    write(1,message.c_str(),message.length());
+    write(1,"\n",1);
+}
+void pipedal::AdminInstallUpdate(const std::filesystem::path path)
+{
+
+    try
+    {
+        fs:create_directories(ROOT_INSTALL_DIRECTORY);
+        Lv2Log::info(SS("Installing " << path));
+
+        if (!path.string().starts_with(UPDATE_DIRECTORY.string()))
+        {
+            throw std::runtime_error("Update file path is incorrect.");
+        }
+        if (!fs::exists(path))
+        {
+            throw std::runtime_error("File does not exist.");
+        }
+
+        std::stringstream ssCmd;
+        ssCmd << "/usr/bin/apt-get -q -y install " << path.string();
+
+        std::string cmd = ssCmd.str();
+
+        // direct standard outputs to a log file.
+        close(0);
+        close(1);
+        close(2);
+
+        int fd = open(INSTALLER_LOG_FILE_PATH.c_str(), O_WRONLY | O_CREAT | O_TRUNC, 0644);
+        dup2(fd, 1); // to stdout
+        dup2(fd, 2); // to stderr
+        close(fd);
+        fd = -1;
+
+        // disconnect std input from parent's stdin.
+        int fdNull = open("/dev/null", O_RDONLY, 0644);
+        dup2(fdNull, 0);
+        close(fdNull);
+
+        updateLog("**Stopping pipedald");
+
+        exec("/usr/bin/systemctl stop pipedald");
+
+        updateLog("** Installing update");
+        int retcode = exec(cmd);
+
+
+        // in case we didn't actually update for some reason.
+        updateLog("** Starting pipedald");
+        exec("/usr/bin/systemctl start pipedald");
+   }
+    catch (const std::exception &e)
+    {
+        updateLog(e.what());
+    }
+}