top(1): format help more nicely

For entries that are duplicates present them nicely rather than showing
two identical help entries. For ' ' present it as SPC

1 files changed, 22 insertions, 5 deletions

diff --git a/usr.bin/top/commands.c b/usr.bin/top/commands.c
index 1c5a0fe84333..5b096141316f 100644
--- a/usr.bin/top/commands.c
+++ b/usr.bin/top/commands.c
@@ -57,16 +57,16 @@ const struct command all_commands[] =
 	{'e', "list errors generated by last \"kill\" or \"renice\" command", false, CMD_errors},
 	{'H', "toggle the displaying of threads", false, CMD_thrtog},
 	{'h', "show this help text", true, CMD_help},
-	{'?', "show this help text", true, CMD_help},
+	{'?', NULL, true, CMD_help},
 	{'i', "toggle the displaying of idle processes", false, CMD_idletog},
-	{'I', "toggle the displaying of idle processes", false, CMD_idletog},
+	{'I', NULL, false, CMD_idletog},
 	{'j', "toggle the displaying of jail ID", false, CMD_jidtog},
 	{'J', "display processes for only one jail (+ selects all jails)", false, CMD_jail},
 	{'k', "kill processes; send a signal to a list of processes", false, CMD_kill},
 	{'q', "quit" , true, CMD_quit},
 	{'m', "toggle the display between 'cpu' and 'io' modes", false, CMD_viewtog},
 	{'n', "change number of processes to display", false, CMD_number},
-	{'#', "change number of processes to display", false, CMD_number},
+	{'#', NULL, false, CMD_number},
 	{'o', "specify the sort order", false, CMD_order},
 	{'p', "display one process (+ selects all processes)", false, CMD_pid},
 	{'P', "toggle the displaying of per-CPU statistics", false, CMD_pcputog},
@@ -86,7 +86,9 @@ const struct command all_commands[] =
 void
 show_help(void)
 {
-	const struct command *curcmd;
+	const struct command *curcmd, *nextcmd;
+	char keys[8] = "";
+	_Static_assert(sizeof(keys) >= sizeof("a or b"), "keys right size");
 
     printf("Top version FreeBSD, %s\n", copyright);
 	curcmd = all_commands;
@@ -95,7 +97,22 @@ show_help(void)
 			++curcmd;
 			continue;
 		}
-		printf("%c\t- %s\n", curcmd->c, curcmd->desc);
+		if (curcmd->desc == NULL) {
+			/* we already printed this */
+			++curcmd;
+			continue;
+		}
+		nextcmd = curcmd + 1;
+		if (nextcmd->desc == NULL && nextcmd->c != '\0') {
+			sprintf(keys, "%c or %c", curcmd->c, nextcmd->c);
+		} else if (curcmd->c == ' '){
+			/* special case space rather than introducing a "display string" to
+			 * the struct */
+			sprintf(keys, "SPC");
+		} else {
+			sprintf(keys, "%c", curcmd->c);
+		}
+		printf("%s\t- %s\n", keys, curcmd->desc);
 		++curcmd;
 	}
     if (overstrike)