use separate window/screen to show long commands in multiple lines

Action.c

@@ -13,6 +13,7 @@ in the source distribution for its full text.
 #include "CategoriesPanel.h"
 #include "CRT.h"
 #include "EnvScreen.h"
+#include "CommandScreen.h"
 #include "MainPanel.h"
 #include "OpenFilesScreen.h"
 #include "Process.h"
@@ -422,8 +423,8 @@ static const struct { const char* key; const char* info; } helpRight[] = {
    { .key = "      e: ", .info = "show process environment" },
    { .key = "      i: ", .info = "set IO priority" },
    { .key = "      l: ", .info = "list open files with lsof" },
+   { .key = "      M: ", .info = "show process command in multiple lines" },
    { .key = "      s: ", .info = "trace syscalls with strace" },
-   { .key = "         ", .info = "" },
    { .key = " F2 C S: ", .info = "setup" },
    { .key = "   F1 h: ", .info = "show this help screen" },
    { .key = "  F10 q: ", .info = "quit" },
@@ -530,6 +531,16 @@ static Htop_Reaction actionShowEnvScreen(State* st) {
    return HTOP_REFRESH | HTOP_REDRAW_BAR;
 }
 
+static Htop_Reaction actionShowCommandScreen(State* st) {
+   Process* p = (Process*) Panel_getSelected(st->panel);
+   if (!p) return HTOP_OK;
+   CommandScreen* cmdScr = CommandScreen_new(p);
+   InfoScreen_run((InfoScreen*)cmdScr);
+   CommandScreen_delete((Object*)cmdScr);
+   clear();
+   CRT_enableDelay();
+   return HTOP_REFRESH | HTOP_REDRAW_BAR;
+}
 
 void Action_setBindings(Htop_Action* keys) {
    keys[KEY_RESIZE] = actionResize;
@@ -584,4 +595,5 @@ void Action_setBindings(Htop_Action* keys) {
    keys['U'] = actionUntagAll;
    keys['c'] = actionTagAllChildren;
    keys['e'] = actionShowEnvScreen;
+   keys['M'] = actionShowCommandScreen;
 }

CommandScreen.c

@@ -0,0 +1,74 @@
+#include "CommandScreen.h"
+
+#include "config.h"
+#include "CRT.h"
+#include "IncSet.h"
+#include "ListItem.h"
+#include "Platform.h"
+#include "StringUtils.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+
+static void CommandScreen_addLine(InfoScreen* this, char* line, const char* p, int line_offset, int len) {
+   memcpy(line, p - line_offset, len);
+   line[len] = '\0';
+   InfoScreen_addLine(this, line);
+}
+
+static void CommandScreen_scan(InfoScreen* this) {
+   Panel* panel = this->display;
+   int idx = MAXIMUM(Panel_getSelectedIndex(panel), 0);
+
+   Panel_prune(panel);
+
+   const char* p = this->process->comm;
+   char* line = xMalloc(COLS + 1);
+   int line_offset = 0, last_spc = -1, len;
+   for (; *p != '\0'; p++, line_offset++) {
+      if (*p == ' ') last_spc = line_offset;
+
+      if (line_offset == COLS) {
+         len = (last_spc == -1) ? line_offset : last_spc;
+         CommandScreen_addLine(this, line, p, line_offset, len);
+         line_offset -= len;
+         last_spc = -1;
+      }
+   }
+
+   if (line_offset > 0) CommandScreen_addLine(this, line, p, line_offset, line_offset);
+
+   free(line);
+   Panel_setSelected(panel, idx);
+}
+
+static void CommandScreen_draw(InfoScreen* this) {
+   char* title = xMalloc(COLS + 1);
+   int len = snprintf(title, COLS + 1, "Command of process %d - %s", this->process->pid, this->process->comm);
+   if (len > COLS) {
+      memset(&title[COLS - 3], '.', 3);
+   }
+
+   InfoScreen_drawTitled(this, "%s", title);
+   free(title);
+}
+
+InfoScreenClass CommandScreen_class = {
+   .super = {
+      .extends = Class(Object),
+      .delete = CommandScreen_delete
+   },
+   .scan = CommandScreen_scan,
+   .draw = CommandScreen_draw
+};
+
+CommandScreen* CommandScreen_new(Process* process) {
+   CommandScreen* this = AllocThis(CommandScreen);
+   return (CommandScreen*) InfoScreen_init(&this->super, process, NULL, LINES - 3, " ");
+}
+
+void CommandScreen_delete(Object* this) {
+   free(InfoScreen_done((InfoScreen*)this));
+}

CommandScreen.h

@@ -0,0 +1,16 @@
+#ifndef HEADER_CommandScreen
+#define HEADER_CommandScreen
+
+#include "InfoScreen.h"
+
+typedef struct CommandScreen_ {
+   InfoScreen super;
+} CommandScreen;
+
+extern InfoScreenClass CommandScreen_class;
+
+CommandScreen* CommandScreen_new(Process* process);
+
+void CommandScreen_delete(Object* this);
+
+#endif

Makefile.am

@@ -22,7 +22,7 @@ BatteryMeter.c Process.c ProcessList.c RichString.c ScreenManager.c Settings.c \
 SignalsPanel.c StringUtils.c SwapMeter.c TasksMeter.c UptimeMeter.c \
 TraceScreen.c UsersTable.c Vector.c AvailableColumnsPanel.c AffinityPanel.c \
 HostnameMeter.c OpenFilesScreen.c Affinity.c IncSet.c Action.c EnvScreen.c \
-InfoScreen.c XAlloc.c
+InfoScreen.c CommandScreen.c XAlloc.c
 
 myhtopheaders = AvailableColumnsPanel.h AvailableMetersPanel.h \
 CategoriesPanel.h CheckItem.h ClockMeter.h ColorsPanel.h ColumnsPanel.h \
@@ -32,7 +32,7 @@ BatteryMeter.h Meter.h MetersPanel.h Object.h Panel.h ProcessList.h RichString.h
 ScreenManager.h Settings.h SignalsPanel.h StringUtils.h SwapMeter.h \
 TasksMeter.h UptimeMeter.h TraceScreen.h UsersTable.h Vector.h Process.h \
 AffinityPanel.h HostnameMeter.h OpenFilesScreen.h Affinity.h IncSet.h Action.h \
-EnvScreen.h InfoScreen.h XAlloc.h Macros.h
+EnvScreen.h InfoScreen.h CommandScreen.h XAlloc.h Macros.h
 
 # Linux
 # -----

htop.1.in

@@ -116,6 +116,9 @@ update of system calls issued by the process.
 Display open files for a process: if lsof(1) is installed, pressing this key
 will display the list of file descriptors opened by the process.
 .TP
+.B M
+Display the command line of the highlighted process in multiple lines.
+.TP
 .B F1, h, ?
 Go to the help screen
 .TP