Added CProcessStatisticsReader to avoid having to parse /proc/all (#35)

* Added CProcessStatisticsReader to avoid having to parse /proc/all

* Took @awesomekling's feedbacks into account

* Fixed indentation and replaced tabs by spaces

LibCore/CProcessStatisticsReader.cpp

@@ -0,0 +1,100 @@
+#include "CProcessStatisticsReader.h"
+#include "CFile.h"
+
+#include <stdio.h>
+#include <pwd.h>
+
+CProcessStatisticsReader::CProcessStatisticsReader()
+{
+    setpwent();
+    while (auto* passwd = getpwent())
+        m_usernames.set(passwd->pw_uid, passwd->pw_name);
+    endpwent();
+}
+
+HashMap<pid_t, CProcessStatistics> CProcessStatisticsReader::get_map()
+{
+    HashMap<pid_t, CProcessStatistics> res;
+    update_map(res);
+    return res;
+}
+
+void CProcessStatisticsReader::update_map(HashMap<pid_t, CProcessStatistics>& map)
+{
+    CFile file("/proc/all");
+    if (!file.open(CIODevice::ReadOnly)) {
+        fprintf(stderr, "CProcessHelper : failed to open /proc/all: %s\n", file.error_string());
+        return;
+    }
+
+    for (;;) {
+        auto line = file.read_line(1024);
+
+        if (line.is_empty())
+            break;
+
+        auto chomped = String((const char*)line.pointer(), line.size() - 1, Chomp);
+        auto parts = chomped.split_view(',');
+
+        if (parts.size() < 18)
+            break;
+
+        bool ok = false;
+        CProcessStatistics process;
+
+        process.pid = parts[0].to_uint(ok);
+        if (!ok) {
+            fprintf(stderr, "CProcessHelper : couldn't convert %s to a valid pid\n", parts[0].characters());
+            return;
+        }
+
+        process.nsched = parts[1].to_uint(ok);
+        if (!ok) {
+            fprintf(stderr, "CProcessHelper : couldn't convert %s to a valid nsched value\n", parts[1].characters());
+            return;
+        }
+
+        uid_t uid = parts[5].to_uint(ok);
+        if (!ok) {
+            fprintf(stderr, "CProcessHelper : couldn't convert %s to a valid uid value\n", parts[5].characters());
+            return;
+        }
+
+        process.uid = uid;
+        process.username = get_username_from_uid(uid);
+
+        process.priority = parts[16];
+        
+        process.syscalls = parts[17].to_uint(ok);
+        if (!ok) {
+            fprintf(stderr, "CProcessHelper : couldn't convert %s to a valid syscalls count value\n", parts[17].characters());
+            return;
+        }
+
+        process.state = parts[7];
+
+        process.name = parts[11];
+        process.linear = parts[12].to_uint(ok);
+        if (!ok) {
+            fprintf(stderr, "CProcessHelper : couldn't convert %s to a valid amount of linear address space used\n", parts[12].characters());
+            return;
+        }
+
+        process.physical = parts[13].to_uint(ok);
+        if (!ok) {
+            fprintf(stderr, "CProcessHelper : couldn't convert %s to a valid amount of physical address space used\n", parts[13].characters());
+            return;
+        }
+
+        map.set(process.pid, process);
+    }
+}
+
+String CProcessStatisticsReader::get_username_from_uid(const uid_t uid)
+{
+    auto it = m_usernames.find(uid);
+    if (it != m_usernames.end())
+        return (*it).value;
+    else
+        return String::format("%u", uid);
+}

LibCore/CProcessStatisticsReader.h

@@ -0,0 +1,29 @@
+#pragma once
+
+#include <AK/AKString.h>
+#include <AK/HashMap.h>
+
+struct CProcessStatistics {
+    pid_t pid;
+    unsigned nsched;
+    String name;
+    String state;
+    String username;
+    uid_t uid;
+    String priority;
+    size_t linear;
+    size_t physical;
+    unsigned syscalls;
+};
+
+class CProcessStatisticsReader {
+public:
+    CProcessStatisticsReader();
+    HashMap<pid_t, CProcessStatistics> get_map();
+
+private:
+    void update_map(HashMap<pid_t, CProcessStatistics>& map);
+    String get_username_from_uid(const uid_t uid);
+  
+    HashMap<uid_t, String> m_usernames;
+};

LibCore/Makefile

@@ -16,7 +16,8 @@ OBJS = \
     CTimer.o \
     CEventLoop.o \
     CConfigFile.o \
-    CEvent.o
+    CEvent.o \
+    CProcessStatisticsReader.o
 
 LIBRARY = libcore.a
 DEFINES += -DUSERLAND

Userland/killall.cpp

@@ -2,7 +2,7 @@
 #include <stdio.h>
 #include <signal.h>
 #include <stdlib.h>
-#include <LibCore/CFile.h>
+#include <LibCore/CProcessStatisticsReader.h>
 #include <AK/AKString.h>
 
 static void print_usage_and_exit()
@@ -13,40 +13,16 @@ static void print_usage_and_exit()
 
 static int kill_all(const String& process_name, const unsigned signum)
 {
-    CFile file("/proc/all");
-    if (!file.open(CIODevice::ReadOnly)) {
-	fprintf(stderr, "killall failed to open /proc/all\n");
-	return 3;
+    HashMap<pid_t, CProcessStatistics> processes = CProcessStatisticsReader().get_map();
+    
+    for (auto& it : processes) {
+        if (it.value.name == process_name) {    
+            int ret = kill(it.value.pid, signum);
+            if (ret < 0)
+                perror("kill");
+        }
     }
-
-    for (;;) {
-	auto line = file.read_line(1024);
-      
-	if (line.is_empty())
-	    break;
-
-	auto chomped = String((const char*)line.pointer(), line.size() - 1, Chomp);
-	auto parts = chomped.split_view(',');
-
-	if (parts.size() < 18)
-	    break;
-
-	bool ok = false;
-	pid_t pid = parts[0].to_uint(ok);
-	String name = parts[11];
-
-	if (!ok) {
-	    fprintf(stderr, "killall failed : couldn't convert %s to a valid pid\n", parts[0].characters());
-	    return 4;
-	}
-      
-	if (name == process_name) {	
-	    int ret = kill(pid, signum);
-	    if (ret < 0)
-		perror("kill");
-	}
-    }
-
+  
     return 0;
 }
 
@@ -60,12 +36,12 @@ int main(int argc, char** argv)
         print_usage_and_exit();
         
     if (argc == 3) {
-	name_argi = 2;
-      
+        name_argi = 2;
+        
         if (argv[1][0] != '-')
             print_usage_and_exit();
-	
-	signum = String(&argv[1][1]).to_uint(ok);
+        
+        signum = String(&argv[1][1]).to_uint(ok);
         if (!ok) {
             printf("'%s' is not a valid signal number\n", &argv[1][1]);
             return 2;

Userland/pidof.cpp

@@ -2,55 +2,32 @@
 #include <stdio.h>
 #include <signal.h>
 #include <stdlib.h>
-#include <LibCore/CFile.h>
+#include <LibCore/CProcessStatisticsReader.h>
 #include <AK/AKString.h>
 #include <AK/Vector.h>
 #include <AK/ArgsParser.h>
+#include <AK/HashMap.h>
 
 static int pid_of(const String& process_name, bool single_shot, bool omit_pid, pid_t pid)
 {
     bool displayed_at_least_one = false;
 
-    CFile file("/proc/all");
-    if (!file.open(CIODevice::ReadOnly)) {
-	fprintf(stderr, "pidof failed to open /proc/all\n");
-	return 2;
-    }
+    HashMap<pid_t, CProcessStatistics> processes = CProcessStatisticsReader().get_map();
+    
+    for (auto& it : processes) {
+        if (it.value.name == process_name) {    
+            if (!omit_pid || (omit_pid && it.value.pid != pid)) {
+                printf("%d ", it.value.pid);
+                displayed_at_least_one = true;
 
-    for (;;) {
-	auto line = file.read_line(1024);
-		
-	if (line.is_empty())
-	    break;
-
-	auto chomped = String((const char*)line.pointer(), line.size() - 1, Chomp);
-	auto parts = chomped.split_view(',');
-
-	if (parts.size() < 18)
-	    break;
-
-	bool ok = false;
-	pid_t current_pid = parts[0].to_uint(ok);
-	String name = parts[11];
-
-	if (!ok) {
-	    fprintf(stderr, "pidof failed : couldn't convert %s to a valid pid\n", parts[0].characters());
-	    return 3;
-	}
-		
-	if (name == process_name) {	
-	    if (!omit_pid || (omit_pid && current_pid != pid)) {
-		printf("%d ", current_pid);
-		displayed_at_least_one = true;
-
-		if (single_shot)
-		    break;
-	    }
-	}
+                if (single_shot)
+                    break;
+            }
+        }
     }
 
     if (displayed_at_least_one)
-	printf("\n");
+        printf("\n");
 
     return 0;
 }
@@ -72,16 +49,16 @@ int main(int argc, char** argv)
         bool ok = false;
         String pid_str = args.get("o");
 
-	if (pid_str == "%PPID")
-	    pid = getppid();
-	else
-	    pid = pid_str.to_uint(ok);
+        if (pid_str == "%PPID")
+            pid = getppid();
+        else
+            pid = pid_str.to_uint(ok);
     }
     
     // We should have one single value : the process name
     Vector<String> values = args.get_single_values();
     if (values.size() == 0) {
-	args_parser.print_usage();
+        args_parser.print_usage();
         return 0;
     }