bpftool: Support "opcodes", "linum", "visual" simultaneously

When dumping a program, the keywords "opcodes" (for printing the raw
opcodes), "linum" (for displaying the filename, line number, column
number along with the source code), and "visual" (for generating the
control flow graph for translated programs) are mutually exclusive. But
there's no reason why they should be. Let's make it possible to pass
several of them at once. The "file FILE" option, which makes bpftool
output a binary image to a file, remains incompatible with the others.

Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Link: https://lore.kernel.org/r/20230405132120.59886-6-quentin@isovalent.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

tools/bpf/bpftool/Documentation/bpftool-prog.rst

@@ -28,8 +28,8 @@ PROG COMMANDS
 =============
 
 |	**bpftool** **prog** { **show** | **list** } [*PROG*]
-|	**bpftool** **prog dump xlated** *PROG* [{**file** *FILE* | **opcodes** | **visual** | **linum**}]
-|	**bpftool** **prog dump jited**  *PROG* [{**file** *FILE* | **opcodes** | **linum**}]
+|	**bpftool** **prog dump xlated** *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] [**visual**] }]
+|	**bpftool** **prog dump jited**  *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] }]
 |	**bpftool** **prog pin** *PROG* *FILE*
 |	**bpftool** **prog** { **load** | **loadall** } *OBJ* *PATH* [**type** *TYPE*] [**map** {**idx** *IDX* | **name** *NAME*} *MAP*] [**dev** *NAME*] [**pinmaps** *MAP_DIR*] [**autoattach**]
 |	**bpftool** **prog attach** *PROG* *ATTACH_TYPE* [*MAP*]
@@ -88,7 +88,7 @@ DESCRIPTION
 		  programs. On such kernels bpftool will automatically emit this
 		  information as well.
 
-	**bpftool prog dump xlated** *PROG* [{ **file** *FILE* | **opcodes** | **visual** | **linum** }]
+	**bpftool prog dump xlated** *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] [**visual**] }]
 		  Dump eBPF instructions of the programs from the kernel. By
 		  default, eBPF will be disassembled and printed to standard
 		  output in human-readable format. In this case, **opcodes**
@@ -109,7 +109,7 @@ DESCRIPTION
 		  be displayed.  If **linum** is specified, the filename, line
 		  number and line column will also be displayed.
 
-	**bpftool prog dump jited**  *PROG* [{ **file** *FILE* | **opcodes** | **linum** }]
+	**bpftool prog dump jited**  *PROG* [{ **file** *FILE* | [**opcodes**] [**linum**] }]
 		  Dump jited image (host machine code) of the program.
 
 		  If *FILE* is specified image will be written to a file,

tools/bpf/bpftool/bash-completion/bpftool

@@ -271,7 +271,7 @@ _bpftool()
 
     # Deal with simplest keywords
     case $prev in
-        help|hex|opcodes|visual|linum)
+        help|hex)
             return 0
             ;;
         tag)
@@ -369,13 +369,16 @@ _bpftool()
                             return 0
                             ;;
                         *)
-                            _bpftool_once_attr 'file'
+                            # "file" is not compatible with other keywords here
+                            if _bpftool_search_list 'file'; then
+                                return 0
+                            fi
+                            if ! _bpftool_search_list 'linum opcodes visual'; then
+                                _bpftool_once_attr 'file'
+                            fi
+                            _bpftool_once_attr 'linum opcodes'
                             if _bpftool_search_list 'xlated' && [[ "$json" == 0 ]]; then
-                                COMPREPLY+=( $( compgen -W 'opcodes visual linum' -- \
-                                    "$cur" ) )
-                            else
-                                COMPREPLY+=( $( compgen -W 'opcodes linum' -- \
-                                    "$cur" ) )
+                                _bpftool_once_attr 'visual'
                             fi
                             return 0
                             ;;

tools/bpf/bpftool/prog.c

@@ -905,37 +905,42 @@ static int do_dump(int argc, char **argv)
 	if (nb_fds < 1)
 		goto exit_free;
 
-	if (is_prefix(*argv, "file")) {
-		NEXT_ARG();
-		if (!argc) {
-			p_err("expected file path");
-			goto exit_close;
-		}
-		if (nb_fds > 1) {
-			p_err("several programs matched");
-			goto exit_close;
-		}
+	while (argc) {
+		if (is_prefix(*argv, "file")) {
+			NEXT_ARG();
+			if (!argc) {
+				p_err("expected file path");
+				goto exit_close;
+			}
+			if (nb_fds > 1) {
+				p_err("several programs matched");
+				goto exit_close;
+			}
 
-		filepath = *argv;
-		NEXT_ARG();
-	} else if (is_prefix(*argv, "opcodes")) {
-		opcodes = true;
-		NEXT_ARG();
-	} else if (is_prefix(*argv, "visual")) {
-		if (nb_fds > 1) {
-			p_err("several programs matched");
+			filepath = *argv;
+			NEXT_ARG();
+		} else if (is_prefix(*argv, "opcodes")) {
+			opcodes = true;
+			NEXT_ARG();
+		} else if (is_prefix(*argv, "visual")) {
+			if (nb_fds > 1) {
+				p_err("several programs matched");
+				goto exit_close;
+			}
+
+			visual = true;
+			NEXT_ARG();
+		} else if (is_prefix(*argv, "linum")) {
+			linum = true;
+			NEXT_ARG();
+		} else {
+			usage();
 			goto exit_close;
 		}
-
-		visual = true;
-		NEXT_ARG();
-	} else if (is_prefix(*argv, "linum")) {
-		linum = true;
-		NEXT_ARG();
 	}
 
-	if (argc) {
-		usage();
+	if (filepath && (opcodes || visual || linum)) {
+		p_err("'file' is not compatible with 'opcodes', 'visual', or 'linum'");
 		goto exit_close;
 	}
 	if (json_output && visual) {
@@ -2419,8 +2424,8 @@ static int do_help(int argc, char **argv)
 
 	fprintf(stderr,
 		"Usage: %1$s %2$s { show | list } [PROG]\n"
-		"       %1$s %2$s dump xlated PROG [{ file FILE | opcodes | visual | linum }]\n"
-		"       %1$s %2$s dump jited  PROG [{ file FILE | opcodes | linum }]\n"
+		"       %1$s %2$s dump xlated PROG [{ file FILE | [opcodes] [linum] [visual] }]\n"
+		"       %1$s %2$s dump jited  PROG [{ file FILE | [opcodes] [linum] }]\n"
 		"       %1$s %2$s pin   PROG FILE\n"
 		"       %1$s %2$s { load | loadall } OBJ  PATH \\\n"
 		"                         [type TYPE] [dev NAME] \\\n"