LibCore: Make ProcessStatisticsReader return results in a Vector

The HashMap API was overkill and made using this less ergonomic than
it should be.

Userland/Applets/ResourceGraph/main.cpp

@@ -130,8 +130,8 @@ private:
             return false;
 
         for (auto& it : all_processes.value()) {
-            for (auto& jt : it.value.threads) {
-                if (it.value.pid == 0)
+            for (auto& jt : it.threads) {
+                if (it.pid == 0)
                     idle += jt.ticks_user + jt.ticks_kernel;
                 else
                     busy += jt.ticks_user + jt.ticks_kernel;

Userland/Applications/SystemMonitor/ProcessModel.cpp

@@ -328,14 +328,14 @@ void ProcessModel::update()
     HashTable<int> live_tids;
     u64 sum_ticks_scheduled = 0, sum_ticks_scheduled_kernel = 0;
     if (all_processes.has_value()) {
-        for (auto& it : all_processes.value()) {
-            for (auto& thread : it.value.threads) {
+        for (auto& process : all_processes.value()) {
+            for (auto& thread : process.threads) {
                 ThreadState state;
-                state.kernel = it.value.kernel;
-                state.pid = it.value.pid;
-                state.user = it.value.username;
-                state.pledge = it.value.pledge;
-                state.veil = it.value.veil;
+                state.kernel = process.kernel;
+                state.pid = process.pid;
+                state.user = process.username;
+                state.pledge = process.pledge;
+                state.veil = process.veil;
                 state.syscall_count = thread.syscall_count;
                 state.inode_faults = thread.inode_faults;
                 state.zero_faults = thread.zero_faults;
@@ -346,20 +346,20 @@ void ProcessModel::update()
                 state.ipv4_socket_write_bytes = thread.ipv4_socket_write_bytes;
                 state.file_read_bytes = thread.file_read_bytes;
                 state.file_write_bytes = thread.file_write_bytes;
-                state.amount_virtual = it.value.amount_virtual;
-                state.amount_resident = it.value.amount_resident;
-                state.amount_dirty_private = it.value.amount_dirty_private;
-                state.amount_clean_inode = it.value.amount_clean_inode;
-                state.amount_purgeable_volatile = it.value.amount_purgeable_volatile;
-                state.amount_purgeable_nonvolatile = it.value.amount_purgeable_nonvolatile;
+                state.amount_virtual = process.amount_virtual;
+                state.amount_resident = process.amount_resident;
+                state.amount_dirty_private = process.amount_dirty_private;
+                state.amount_clean_inode = process.amount_clean_inode;
+                state.amount_purgeable_volatile = process.amount_purgeable_volatile;
+                state.amount_purgeable_nonvolatile = process.amount_purgeable_nonvolatile;
 
                 state.name = thread.name;
-                state.executable = it.value.executable;
+                state.executable = process.executable;
 
-                state.ppid = it.value.ppid;
+                state.ppid = process.ppid;
                 state.tid = thread.tid;
-                state.pgid = it.value.pgid;
-                state.sid = it.value.sid;
+                state.pgid = process.pgid;
+                state.sid = process.sid;
                 state.ticks_user = thread.ticks_user;
                 state.ticks_kernel = thread.ticks_kernel;
                 state.cpu = thread.cpu;

Userland/DevTools/Profiler/main.cpp

@@ -270,8 +270,8 @@ bool generate_profile(pid_t& pid)
 
     auto all_processes = Core::ProcessStatisticsReader::get_all();
     if (all_processes.has_value()) {
-        if (auto it = all_processes.value().find(pid); it != all_processes.value().end())
-            process_name = it->value.name;
+        if (auto it = all_processes.value().find_if([&](auto& entry) { return entry.pid == pid; }); it != all_processes.value().end())
+            process_name = it->name;
         else
             process_name = "(unknown)";
     } else {

Userland/Libraries/LibCore/ProcessStatisticsReader.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
@@ -17,7 +17,7 @@ namespace Core {
 
 HashMap<uid_t, String> ProcessStatisticsReader::s_usernames;
 
-Optional<HashMap<pid_t, Core::ProcessStatistics>> ProcessStatisticsReader::get_all(RefPtr<Core::File>& proc_all_file)
+Optional<Vector<Core::ProcessStatistics>> ProcessStatisticsReader::get_all(RefPtr<Core::File>& proc_all_file)
 {
     if (proc_all_file) {
         if (!proc_all_file->seek(0, Core::SeekMode::SetPosition)) {
@@ -32,7 +32,7 @@ Optional<HashMap<pid_t, Core::ProcessStatistics>> ProcessStatisticsReader::get_a
         }
     }
 
-    HashMap<pid_t, Core::ProcessStatistics> map;
+    Vector<Core::ProcessStatistics> processes;
 
     auto file_contents = proc_all_file->read_all();
     auto json = JsonValue::from_string(file_contents);
@@ -93,13 +93,13 @@ Optional<HashMap<pid_t, Core::ProcessStatistics>> ProcessStatisticsReader::get_a
 
         // and synthetic data last
         process.username = username_from_uid(process.uid);
-        map.set(process.pid, process);
+        processes.append(move(process));
     });
 
-    return map;
+    return processes;
 }
 
-Optional<HashMap<pid_t, Core::ProcessStatistics>> ProcessStatisticsReader::get_all()
+Optional<Vector<Core::ProcessStatistics>> ProcessStatisticsReader::get_all()
 {
     RefPtr<Core::File> proc_all_file;
     return get_all(proc_all_file);

Userland/Libraries/LibCore/ProcessStatisticsReader.h

@@ -1,12 +1,11 @@
 /*
- * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
+ * Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #pragma once
 
-#include <AK/HashMap.h>
 #include <AK/String.h>
 #include <LibCore/File.h>
 #include <unistd.h>
@@ -67,8 +66,8 @@ struct ProcessStatistics {
 
 class ProcessStatisticsReader {
 public:
-    static Optional<HashMap<pid_t, Core::ProcessStatistics>> get_all(RefPtr<Core::File>&);
-    static Optional<HashMap<pid_t, Core::ProcessStatistics>> get_all();
+    static Optional<Vector<Core::ProcessStatistics>> get_all(RefPtr<Core::File>&);
+    static Optional<Vector<Core::ProcessStatistics>> get_all();
 
 private:
     static String username_from_uid(uid_t);

Userland/Libraries/LibGUI/RunningProcessesModel.cpp

@@ -27,15 +27,14 @@ void RunningProcessesModel::update()
 {
     m_processes.clear();
 
-    Core::ProcessStatisticsReader reader;
-    auto processes = reader.get_all();
+    auto processes = Core::ProcessStatisticsReader::get_all();
     if (processes.has_value()) {
         for (auto& it : processes.value()) {
             Process process;
-            process.pid = it.value.pid;
-            process.uid = it.value.uid;
-            process.icon = FileIconProvider::icon_for_executable(it.value.executable).bitmap_for_size(16);
-            process.name = it.value.name;
+            process.pid = it.pid;
+            process.uid = it.uid;
+            process.icon = FileIconProvider::icon_for_executable(it.executable).bitmap_for_size(16);
+            process.name = it.name;
             m_processes.append(move(process));
         }
     }

Userland/Utilities/killall.cpp

@@ -20,13 +20,13 @@ static void print_usage_and_exit()
 
 static int kill_all(const String& process_name, const unsigned signum)
 {
-    auto processes = Core::ProcessStatisticsReader().get_all();
+    auto processes = Core::ProcessStatisticsReader::get_all();
     if (!processes.has_value())
         return 1;
 
-    for (auto& it : processes.value()) {
-        if (it.value.name == process_name) {
-            int ret = kill(it.value.pid, signum);
+    for (auto& process : processes.value()) {
+        if (process.name == process_name) {
+            int ret = kill(process.pid, signum);
             if (ret < 0)
                 perror("kill");
         }

Userland/Utilities/lsof.cpp

@@ -150,22 +150,22 @@ int main(int argc, char* argv[])
     if (!processes.has_value())
         return 1;
     if (arg_pid == -1) {
-        for (auto process : processes.value()) {
-            if (process.key == 0)
+        for (auto& process : processes.value()) {
+            if (process.pid == 0)
                 continue;
-            auto open_files = get_open_files_by_pid(process.key);
+            auto open_files = get_open_files_by_pid(process.pid);
 
             if (open_files.is_empty())
                 continue;
 
-            for (auto file : open_files) {
+            for (auto& file : open_files) {
                 if ((arg_all_processes)
                     || (arg_fd != -1 && file.fd == arg_fd)
-                    || (arg_uid_int != -1 && (int)process.value.uid == arg_uid_int)
-                    || (arg_uid != nullptr && process.value.username == arg_uid)
-                    || (arg_pgid != -1 && (int)process.value.pgid == arg_pgid)
+                    || (arg_uid_int != -1 && (int)process.uid == arg_uid_int)
+                    || (arg_uid != nullptr && process.username == arg_uid)
+                    || (arg_pgid != -1 && (int)process.pgid == arg_pgid)
                     || (arg_filename != nullptr && file.name == arg_filename))
-                    display_entry(file, process.value);
+                    display_entry(file, process);
             }
         }
     } else {
@@ -175,7 +175,7 @@ int main(int argc, char* argv[])
             return 0;
 
         for (auto file : open_files) {
-            display_entry(file, processes.value().get(arg_pid).value());
+            display_entry(file, *processes->find_if([&](auto& entry) { return entry.pid == arg_pid; }));
         }
     }
 

Userland/Utilities/pidof.cpp

@@ -19,14 +19,14 @@ static int pid_of(const String& process_name, bool single_shot, bool omit_pid, p
 {
     bool displayed_at_least_one = false;
 
-    auto processes = Core::ProcessStatisticsReader().get_all();
+    auto processes = Core::ProcessStatisticsReader::get_all();
     if (!processes.has_value())
         return 1;
 
     for (auto& it : processes.value()) {
-        if (it.value.name == process_name) {
-            if (!omit_pid || it.value.pid != pid) {
-                printf(" %d" + (displayed_at_least_one ? 0 : 1), it.value.pid);
+        if (it.name == process_name) {
+            if (!omit_pid || it.pid != pid) {
+                printf(" %d" + (displayed_at_least_one ? 0 : 1), it.pid);
                 displayed_at_least_one = true;
 
                 if (single_shot)

Userland/Utilities/ps.cpp

@@ -103,9 +103,8 @@ int main(int argc, char** argv)
     if (!all_processes.has_value())
         return 1;
 
-    for (const auto& it : all_processes.value()) {
-        const auto& proc = it.value;
-        auto tty = proc.tty;
+    for (auto const& process : all_processes.value()) {
+        auto tty = process.tty;
 
         if (!every_process_flag && tty != this_tty)
             continue;
@@ -115,20 +114,20 @@ int main(int argc, char** argv)
         else
             tty = "n/a";
 
-        auto* state = proc.threads.is_empty() ? "Zombie" : proc.threads.first().state.characters();
+        auto* state = process.threads.is_empty() ? "Zombie" : process.threads.first().state.characters();
 
         if (uid_column != -1)
-            columns[uid_column].buffer = proc.username;
+            columns[uid_column].buffer = process.username;
         if (pid_column != -1)
-            columns[pid_column].buffer = String::number(proc.pid);
+            columns[pid_column].buffer = String::number(process.pid);
         if (ppid_column != -1)
-            columns[ppid_column].buffer = String::number(proc.ppid);
+            columns[ppid_column].buffer = String::number(process.ppid);
         if (tty_column != -1)
             columns[tty_column].buffer = tty;
         if (state_column != -1)
             columns[state_column].buffer = state;
         if (cmd_column != -1)
-            columns[cmd_column].buffer = proc.name;
+            columns[cmd_column].buffer = process.name;
 
         for (auto& column : columns)
             print_column(column, column.buffer);

Userland/Utilities/top.cpp

@@ -77,25 +77,24 @@ static Snapshot get_snapshot()
         return {};
 
     Snapshot snapshot;
-    for (auto& it : all_processes.value()) {
-        auto& stats = it.value;
-        for (auto& thread : stats.threads) {
+    for (auto& process : all_processes.value()) {
+        for (auto& thread : process.threads) {
             snapshot.sum_times_scheduled += thread.times_scheduled;
             ThreadData thread_data;
             thread_data.tid = thread.tid;
-            thread_data.pid = stats.pid;
-            thread_data.pgid = stats.pgid;
-            thread_data.pgp = stats.pgp;
-            thread_data.sid = stats.sid;
-            thread_data.uid = stats.uid;
-            thread_data.gid = stats.gid;
-            thread_data.ppid = stats.ppid;
-            thread_data.nfds = stats.nfds;
-            thread_data.name = stats.name;
-            thread_data.tty = stats.tty;
-            thread_data.amount_virtual = stats.amount_virtual;
-            thread_data.amount_resident = stats.amount_resident;
-            thread_data.amount_shared = stats.amount_shared;
+            thread_data.pid = process.pid;
+            thread_data.pgid = process.pgid;
+            thread_data.pgp = process.pgp;
+            thread_data.sid = process.sid;
+            thread_data.uid = process.uid;
+            thread_data.gid = process.gid;
+            thread_data.ppid = process.ppid;
+            thread_data.nfds = process.nfds;
+            thread_data.name = process.name;
+            thread_data.tty = process.tty;
+            thread_data.amount_virtual = process.amount_virtual;
+            thread_data.amount_resident = process.amount_resident;
+            thread_data.amount_shared = process.amount_shared;
             thread_data.syscall_count = thread.syscall_count;
             thread_data.inode_faults = thread.inode_faults;
             thread_data.zero_faults = thread.zero_faults;
@@ -103,9 +102,9 @@ static Snapshot get_snapshot()
             thread_data.times_scheduled = thread.times_scheduled;
             thread_data.priority = thread.priority;
             thread_data.state = thread.state;
-            thread_data.username = stats.username;
+            thread_data.username = process.username;
 
-            snapshot.map.set({ stats.pid, thread.tid }, move(thread_data));
+            snapshot.map.set({ process.pid, thread.tid }, move(thread_data));
         }
     }
 

Userland/Utilities/w.cpp

@@ -95,9 +95,9 @@ int main()
 
         String what = "n/a";
 
-        for (auto& it : process_statistics.value()) {
-            if (it.value.tty == tty && it.value.pid == it.value.pgid)
-                what = it.value.name;
+        for (auto& process : process_statistics.value()) {
+            if (process.tty == tty && process.pid == process.pgid)
+                what = process.name;
         }
 
         printf("%-10s %-12s %-16s %-6s %s\n",