On 2024-10-16 22:26:22+0200, Robin Jarry wrote: > Add a new test utility to convert between bit masks in various formats. "test" or "text" utility? > This can be handy to avoid parsing affinity masks in one's head and/or > to interact with the kernel in a more human friendly way. > > This is a rewrite in C of the bits command from my linux-tools python > package so that it can be more widely available. > > Here is an example: > > ~# cat /sys/kernel/debug/tracing/tracing_cpumask > fffffff,ffffffff,ffffffff,ffffffff > ~# bits -l ,$(cat /sys/kernel/debug/tracing/tracing_cpumask) > 0-128 > ~# bits -g 58,59,120,123 > 9000000,00000000,0c000000,00000000 > ~# bits -g 58,59 > /sys/kernel/debug/tracing/tracing_cpumask > ~# echo 1 > /sys/kernel/debug/tracing/tracing_on > > Add man page and basic tests. > > Link: https://git.sr.ht/~rjarry/linux-tools#bits > Signed-off-by: Robin Jarry <robin@xxxxxxxx> > --- > bash-completion/bits | 21 ++ > meson.build | 11 ++ > tests/commands.sh | 1 + > tests/expected/misc/bits | 0 > tests/expected/misc/bits-and | 1 + > tests/expected/misc/bits-binary | 1 + > tests/expected/misc/bits-default | 1 + > tests/expected/misc/bits-grouped-mask | 1 + > tests/expected/misc/bits-list | 1 + > tests/expected/misc/bits-mask | 1 + > tests/expected/misc/bits-not | 1 + > tests/expected/misc/bits-or | 1 + > tests/expected/misc/bits-overflow | 1 + > tests/expected/misc/bits-parse-mask | 1 + > tests/expected/misc/bits-parse-range | 1 + > tests/expected/misc/bits-stdin | 1 + > tests/expected/misc/bits-xor | 1 + > tests/ts/misc/bits | 82 ++++++++ > text-utils/Makemodule.am | 6 + > text-utils/bits.1.adoc | 147 ++++++++++++++ > text-utils/bits.c | 265 ++++++++++++++++++++++++++ > text-utils/meson.build | 4 + > 22 files changed, 550 insertions(+) > create mode 100644 bash-completion/bits > create mode 100644 tests/expected/misc/bits > create mode 100644 tests/expected/misc/bits-and > create mode 100644 tests/expected/misc/bits-binary > create mode 100644 tests/expected/misc/bits-default > create mode 100644 tests/expected/misc/bits-grouped-mask > create mode 100644 tests/expected/misc/bits-list > create mode 100644 tests/expected/misc/bits-mask > create mode 100644 tests/expected/misc/bits-not > create mode 100644 tests/expected/misc/bits-or > create mode 100644 tests/expected/misc/bits-overflow > create mode 100644 tests/expected/misc/bits-parse-mask > create mode 100644 tests/expected/misc/bits-parse-range > create mode 100644 tests/expected/misc/bits-stdin > create mode 100644 tests/expected/misc/bits-xor > create mode 100755 tests/ts/misc/bits > create mode 100644 text-utils/bits.1.adoc > create mode 100644 text-utils/bits.c ... > +++ b/tests/ts/misc/bits > @@ -0,0 +1,82 @@ > +#!/bin/bash > + > +# > +# Copyright (c) 2024 Robin Jarry > +# > +# This file is part of util-linux. > +# > +# This file is free software; you can redistribute it and/or modify > +# it under the terms of the GNU General Public License as published by > +# the Free Software Foundation; either version 2 of the License, or > +# (at your option) any later version. > +# > +# This file is distributed in the hope that it will be useful, > +# but WITHOUT ANY WARRANTY; without even the implied warranty of > +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > +# GNU General Public License for more details. New files should use SPDX tags. > diff --git a/text-utils/bits.c b/text-utils/bits.c > new file mode 100644 > index 000000000000..6dd0db81a5de > --- /dev/null > +++ b/text-utils/bits.c > @@ -0,0 +1,265 @@ > +/* > + * SPDX-License-Identifier: GPL-2.0-or-later > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + * Copyright (c) 2024 Robin Jarry > + * > + * bits - convert bit masks from/to various formats > + */ > + > +#include <errno.h> > +#include <getopt.h> > +#include <sched.h> > +#include <stdbool.h> > +#include <stdint.h> > +#include <stdio.h> > +#include <string.h> > +#include <unistd.h> > + > +#include "c.h" > +#include "closestream.h" > +#include "cpuset.h" > +#include "nls.h" > +#include "strutils.h" > +#include "strv.h" > + > +typedef enum { > + OP_OR, > + OP_AND, > + OP_NOT, > + OP_XOR, > +} bitvise_op_t; "bitwise"? Also avoid using the _t suffix as it's reserved. "enum bitwise_op" seems clear enough. > + > +static int parse_mask_or_list(const char *cmdline_arg, cpu_set_t *all_bits) > +{ > + bitvise_op_t op = OP_OR; > + cpu_set_t bits, copy; This seems very geared towards cpu masks. What happens if a user wants to use it with very large non-CPU bitmasks, as the tool is advertised as a generic utility? Call the utility "cpumask"? > + char buf[BUFSIZ]; Only use BUFSIZ in cases where the actual value does not matter, for example loops. On musl BUFSIZ == 1024 and this could not be enough fairly soon. > + char *arg = buf; > + > + /* copy to allow modifying the argument contents */ > + strlcpy(buf, cmdline_arg, sizeof(buf)); > + buf[sizeof(buf) - 1] = '\0'; You can just use xstrdup(). > + > + /* strip optional operator first */ > + if (startswith(arg, "&")) { > + op = OP_AND; > + arg++; > + } else if (startswith(arg, "^")) { > + op = OP_XOR; > + arg++; > + } else if (startswith(arg, "~")) { > + op = OP_NOT; > + arg++; > + } else if (startswith(arg, "|")) { > + op = OP_OR; > + arg++; > + } The whole op enum could also be replaced by the actual character, this is all in a single function. op = '&'; ... switch (op) { case '&': } > + > + if (startswith(arg, ",") || startswith(arg, "0x")) { > + if (cpumask_parse(arg, &bits, sizeof(bits)) < 0) > + return -EINVAL; As this is a commandline tool you can call errx() here to kill the process and provide better error information. It would also make the call sequence slightly more simple. > + } else { > + if (cpulist_parse(arg, &bits, sizeof(bits), 1) < 0) > + return -EINVAL; > + } > + > + switch (op) { > + case OP_AND: > + copy = *all_bits; > + CPU_AND(all_bits, ©, &bits); > + break; > + case OP_OR: > + copy = *all_bits; > + CPU_OR(all_bits, ©, &bits); > + break; > + case OP_XOR: > + copy = *all_bits; > + CPU_XOR(all_bits, ©, &bits); > + break; > + case OP_NOT: > + for (int i = 0; i < CPU_SETSIZE; i++) { > + if (CPU_ISSET(i, &bits)) > + CPU_CLR(i, all_bits); > + } > + break; > + } > + > + return 0; > +} > + > +typedef enum { > + MODE_BINARY, > + MODE_GROUPED_MASK, > + MODE_LIST, > + MODE_MASK, > +} output_mode_t; > + > +static void print_bits(cpu_set_t *bits, output_mode_t mode) > +{ > + bool started = false; > + char buf[BUFSIZ]; > + ssize_t n = 0; > + > + buf[0] = '\0'; Is this necessary? > + > + switch (mode) { > + case MODE_MASK: > + cpumask_create(buf, sizeof(buf), bits, sizeof(*bits)); > + > + /* strip leading zeroes */ > + while (buf[n] == '0') > + n++; > + if (buf[n] == '\0') > + printf("0x0\n"); > + else > + printf("0x%s\n", buf + n); > + break; > + > + case MODE_GROUPED_MASK: > + cpumask_create(buf, sizeof(buf), bits, sizeof(*bits)); > + > + /* strip leading zeroes */ > + while (buf[n] == '0') > + n++; > + > + while (buf[n] != '\0') { > + if (started && (n % 8) == 0) > + printf(","); > + if (buf[n] != '0') > + started = true; > + printf("%c", buf[n]); > + n++; > + } > + printf("\n"); > + break; > + > + case MODE_BINARY: > + printf("0b"); > + for (n = CPU_SETSIZE; n >= 0; n--) { > + if (started && ((n + 1) % 4) == 0) > + printf("_"); > + if (CPU_ISSET(n, bits)) { > + started = true; > + printf("1"); > + } else if (started) { > + printf("0"); > + } > + } > + printf("\n"); > + break; > + > + case MODE_LIST: > + cpulist_create(buf, sizeof(buf), bits, sizeof(*bits)); This could use the return values of cpulist_create() and cpumask_create(). > + printf("%s\n", buf); > + break; > + } > + > +} > + > +static void __attribute__((__noreturn__)) usage(void) > +{ > + fputs(USAGE_HEADER, stdout); > + fprintf(stdout, _(" %s [options] [<mask_or_list>...]\n"), program_invocation_short_name); > + > + fputs(USAGE_SEPARATOR, stdout); > + fputsln(_("Convert bit masks from/to various formats."), stdout); > + > + fputs(USAGE_ARGUMENTS, stdout); > + fputsln(_(" <mask_or_list> A set of bits specified as a hex mask value (e.g. 0xeec2)\n" > + " or as a comma-separated list of bit IDs.\n" > + " If not specified, arguments will be read from stdin."), stdout); > + > + fputs(USAGE_OPTIONS, stdout); > + fprintf(stdout, USAGE_HELP_OPTIONS(21)); > + > + fputs(_("\nMode:\n"), stdout); > + fputsln(_(" -m, --mask Print the combined args as a hex mask value (default).\n"), stdout); > + fputsln(_(" -g, --grouped-mask Print the combined args as a hex mask value in 32bit\n" > + " comma separated groups."), stdout); > + fputsln(_(" -b, --binary Print the combined args as a binary mask value."), stdout); > + fputsln(_(" -l, --list Print the combined args as a compressed list of bit IDs."), stdout); > + > + fputs(USAGE_SEPARATOR, stdout); > + fprintf(stdout, USAGE_MAN_TAIL("bits(1)")); > + exit(EXIT_SUCCESS); > +} > + > +int main(int argc, char **argv) > +{ > + output_mode_t mode = MODE_MASK; > + char **stdin_lines = NULL; > + cpu_set_t bits; > + int c; > + > + static const struct option longopts[] = { > + { "version", no_argument, NULL, 'V'}, > + { "help", no_argument, NULL, 'h'}, > + { "mask", no_argument, NULL, 'm'}, > + { "grouped-mask", no_argument, NULL, 'g'}, > + { "binary", no_argument, NULL, 'b'}, > + { "list", no_argument, NULL, 'l'}, > + { NULL, 0, NULL, 0 } > + }; > + > + setlocale(LC_ALL, ""); > + bindtextdomain(PACKAGE, LOCALEDIR); > + textdomain(PACKAGE); > + close_stdout_atexit(); > + > + while ((c = getopt_long(argc, argv, "Vhmgbl", longopts, NULL)) != -1) > + switch (c) { > + case 'm': > + mode = MODE_MASK; > + break; > + case 'g': > + mode = MODE_GROUPED_MASK; > + break; > + case 'b': > + mode = MODE_BINARY; > + break; > + case 'l': > + mode = MODE_LIST; > + break; > + case 'V': > + print_version(EXIT_SUCCESS); > + case 'h': > + usage(); > + default: > + errtryhelp(EXIT_FAILURE); > + } > + > + argc -= optind; > + argv += optind; > + if (argc == 0) { > + /* no arguments provided, read lines from stdin */ > + char buf[BUFSIZ]; > + > + while (fgets(buf, sizeof(buf), stdin)) { > + /* strip LF, CR, CRLF, LFCR */ > + buf[strcspn(buf, "\r\n")] = '\0'; rtrim_whitespace()? > + strv_push(&stdin_lines, strdup(buf)); > + } > + > + argc = strv_length(stdin_lines); > + argv = stdin_lines; > + } > + > + CPU_ZERO(&bits); > + > + for (; argc > 0; argc--, argv++) > + if (parse_mask_or_list(*argv, &bits) < 0) { > + fprintf(stderr, _("error: invalid argument: %s\n"), *argv); > + errtryhelp(EXIT_FAILURE); > + } > + > + strv_free(stdin_lines); No need to free this here. The process will exit anyways. > + > + print_bits(&bits, mode); > + > + return EXIT_SUCCESS; > +}
