Add -p flag, contributed by Rob Hoelz

Panel.c

@@ -250,7 +250,11 @@ void Panel_draw(Panel* this, bool focus) {
    int scrollH = this->scrollH;
    int y = this->y; int x = this->x;
    int first = this->scrollV;
-   int last = MIN(itemCount, this->scrollV + MIN(itemCount, this->h));
+   if (itemCount > this->h && first > itemCount - this->h) {
+      first = itemCount - this->h;
+      this->scrollV = first;
+   }
+   int last = MIN(itemCount, first + MIN(itemCount, this->h));
    if (this->selected < first) {
       first = this->selected;
       this->scrollV = first;

ProcessList.c

@@ -114,6 +114,7 @@ typedef struct ProcessList_ {
    uid_t userId;
    bool filtering;
    const char* incFilter;
+   Hashtable* pidWhiteList;
 
    int cpuCount;
    int totalTasks;
@@ -180,12 +181,13 @@ const char *ProcessList_treeStrUtf8[TREE_STR_COUNT] = {
    "\xe2\x94\x80", // TREE_STR_SHUT ─
 };
 
-ProcessList* ProcessList_new(UsersTable* usersTable) {
+ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidWhiteList) {
    ProcessList* this;
    this = calloc(sizeof(ProcessList), 1);
    this->processes = Vector_new(PROCESS_CLASS, true, DEFAULT_SIZE, Process_compare);
    this->processTable = Hashtable_new(140, false);
    this->usersTable = usersTable;
+   this->pidWhiteList = pidWhiteList;
    
    /* tree-view auxiliary buffers */
    this->processes2 = Vector_new(PROCESS_CLASS, true, DEFAULT_SIZE, Process_compare);
@@ -599,6 +601,7 @@ static void ProcessList_readVServerData(Process* process, const char* dirname, c
 static bool ProcessList_readCmdlineFile(Process* process, const char* dirname, const char* name) {
    if (Process_isKernelThread(process))
       return true;
+
    char filename[MAX_NAME+1];
    snprintf(filename, MAX_NAME, "%s/%s/cmdline", dirname, name);
    FILE* file = fopen(filename, "r");
@@ -617,6 +620,7 @@ static bool ProcessList_readCmdlineFile(Process* process, const char* dirname, c
    fclose(file);
    free(process->comm);
    process->comm = strdup(command);
+
    return true;
 }
 
@@ -928,7 +932,8 @@ void ProcessList_rebuildPanel(ProcessList* this, bool flags, int following, bool
 
       if ( (!p->show)
          || (userOnly && (p->st_uid != userId))
-         || (filtering && !(String_contains_i(p->comm, incFilter))) )
+         || (filtering && !(String_contains_i(p->comm, incFilter)))
+         || (this->pidWhiteList && !Hashtable_get(this->pidWhiteList, p->pid)) )
          hidden = true;
 
       if (!hidden) {

ProcessList.h

@@ -97,6 +97,7 @@ typedef struct ProcessList_ {
    uid_t userId;
    bool filtering;
    const char* incFilter;
+   Hashtable* pidWhiteList;
 
    int cpuCount;
    int totalTasks;
@@ -144,7 +145,7 @@ extern const char *ProcessList_treeStrAscii[TREE_STR_COUNT];
 
 extern const char *ProcessList_treeStrUtf8[TREE_STR_COUNT];
 
-ProcessList* ProcessList_new(UsersTable* usersTable);
+ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidWhiteList);
 
 void ProcessList_delete(ProcessList* this);
 

htop.1.in

@@ -29,12 +29,15 @@ Start htop in monochrome mode
 \fB\-h \-\-help
 Display a help message and exit
 .TP
-\fB\-u \-\-user=USERNAME\fR
-Show only the processes of a given user
+\fB\-p \-\-pid=PID,PID...\fR
+Show only the given PIDs
 .TP
 \fB\-s \-\-sort\-key COLUMN\fR
 Sort by this column (use \-\-sort\-key help for a column list)
 .TP
+\fB\-u \-\-user=USERNAME\fR
+Show only the processes of a given user
+.TP
 \fB\-v \-\-version
 Output version information and exit
 .PP

htop.c

@@ -51,11 +51,12 @@ static void printVersionFlag() {
 static void printHelpFlag() {
    fputs("htop " VERSION " - " COPYRIGHT "\n"
          "Released under the GNU GPL.\n\n"
-         "-C --no-color         Use a monochrome color scheme\n"
-         "-d --delay=DELAY      Set the delay between updates, in tenths of seconds\n"
-         "-h --help             Print this help screen\n"
-         "-s --sort-key=COLUMN  Sort by COLUMN (try --sort-key=help for a list)\n"
-         "-u --user=USERNAME    Show only processes of a given user\n"
+         "-C --no-color               Use a monochrome color scheme\n"
+         "-d --delay=DELAY            Set the delay between updates, in tenths of seconds\n"
+         "-h --help                   Print this help screen\n"
+         "-s --sort-key=COLUMN        Sort by COLUMN (try --sort-key=help for a list)\n"
+         "-u --user=USERNAME          Show only processes of a given user\n"
+         "-p --pid=PID,[,PID,PID...]  Show only the given PIDs\n"
          "-v --version          Print version info\n"
          "\n"
          "Long options may be passed with a single dash.\n\n"
@@ -269,6 +270,9 @@ int main(int argc, char** argv) {
    uid_t userId = 0;
    int usecolors = 1;
    TreeType treeType = TREE_TYPE_AUTO;
+   char *argCopy;
+   char *pid;
+   Hashtable *pidWhiteList = NULL;
 
    int opt, opti=0;
    static struct option long_opts[] =
@@ -280,6 +284,7 @@ int main(int argc, char** argv) {
       {"user",     required_argument,   0, 'u'},
       {"no-color", no_argument,         0, 'C'},
       {"no-colour",no_argument,         0, 'C'},
+      {"pid",      required_argument,   0, 'p'},
       {0,0,0,0}
    };
    int sortKey = 0;
@@ -293,7 +298,7 @@ int main(int argc, char** argv) {
       setlocale(LC_CTYPE, "");
 
    /* Parse arguments */
-   while ((opt = getopt_long(argc, argv, "hvCs:d:u:", long_opts, &opti))) {
+   while ((opt = getopt_long(argc, argv, "hvCs:d:u:p:", long_opts, &opti))) {
       if (opt == EOF) break;
       switch (opt) {
          case 'h':
@@ -332,6 +337,22 @@ int main(int argc, char** argv) {
             break;
          case 'C':
             usecolors=0;
+            break;
+        case 'p':
+            argCopy = strdup(optarg);
+            pid = strtok(argCopy, ",");
+
+            if( !pidWhiteList ) {
+               pidWhiteList = Hashtable_new(8, false);
+            }
+
+            while( pid ) {
+                unsigned int num_pid = atoi(pid);
+                Hashtable_put(pidWhiteList, num_pid, (void *) 1);
+                pid = strtok(NULL, ",");
+            }
+            free(argCopy);
+
             break;
          default:
             exit(1);
@@ -356,7 +377,7 @@ int main(int argc, char** argv) {
    ProcessList* pl = NULL;
    UsersTable* ut = UsersTable_new();
 
-   pl = ProcessList_new(ut);
+   pl = ProcessList_new(ut, pidWhiteList);
    Process_getMaxPid();
    
    Header* header = Header_new(pl);
@@ -936,5 +957,8 @@ int main(int argc, char** argv) {
       ((Object*)killPanel)->delete((Object*)killPanel);
    UsersTable_delete(ut);
    Settings_delete(settings);
+   if(pidWhiteList) {
+      Hashtable_delete(pidWhiteList);
+   }
    return 0;
 }