On Tue, Apr 16, 2013 at 5:39 PM, Tom Gundersen <teg@xxxxxxx> wrote:
> This tool reads modules.devname from the current kernel directory and outputs
> the information. By default in a human-readable format, and optionally in
> machine-readable formats.
>
> For now only the tmpfiles.d(5) format is supported, but more could easily be
> added in the future if there is a need.
>
> This means nothing but kmod needs to reads the private files under
> /lib/modules/. In particular systemd-udevd can stop reading modules.devname.
>
> Tools that used to read /lib/modules/`uname -r`/modules.devname directly, can
> now move to reading 'kmod static-nodes devname'.
>
> ---
>
> v4: refactor to make it easier to add more formats, added the legacy 'devname'
> format as an example.
>
> Makefile.am | 3 +-
> tools/kmod.c | 1 +
> tools/kmod.h | 1 +
> tools/static-nodes.c | 246 +++++++++++++++++++++++++++++++++++++++++++++++++++
> 4 files changed, 250 insertions(+), 1 deletion(-)
> create mode 100644 tools/static-nodes.c
>
> diff --git a/Makefile.am b/Makefile.am
> index fe4c769..b1bfd59 100644
> --- a/Makefile.am
> +++ b/Makefile.am
> @@ -110,7 +110,8 @@ noinst_SCRIPTS = tools/insmod tools/rmmod tools/lsmod \
> tools_kmod_SOURCES = tools/kmod.c tools/kmod.h tools/lsmod.c \
> tools/rmmod.c tools/insmod.c \
> tools/modinfo.c tools/modprobe.c \
> - tools/depmod.c tools/log.h tools/log.c
> + tools/depmod.c tools/log.h tools/log.c \
> + tools/static-nodes.c
> tools_kmod_LDADD = libkmod/libkmod-util.la \
> libkmod/libkmod.la
>
> diff --git a/tools/kmod.c b/tools/kmod.c
> index ebb8875..347bb7d 100644
> --- a/tools/kmod.c
> +++ b/tools/kmod.c
> @@ -37,6 +37,7 @@ static const struct kmod_cmd kmod_cmd_help;
> static const struct kmod_cmd *kmod_cmds[] = {
> &kmod_cmd_help,
> &kmod_cmd_list,
> + &kmod_cmd_static_nodes,
> };
>
> static const struct kmod_cmd *kmod_compat_cmds[] = {
> diff --git a/tools/kmod.h b/tools/kmod.h
> index 80fa4c2..68a646a 100644
> --- a/tools/kmod.h
> +++ b/tools/kmod.h
> @@ -35,5 +35,6 @@ extern const struct kmod_cmd kmod_cmd_compat_modprobe;
> extern const struct kmod_cmd kmod_cmd_compat_depmod;
>
> extern const struct kmod_cmd kmod_cmd_list;
> +extern const struct kmod_cmd kmod_cmd_static_nodes;
>
> #include "log.h"
> diff --git a/tools/static-nodes.c b/tools/static-nodes.c
> new file mode 100644
> index 0000000..94a48c6
> --- /dev/null
> +++ b/tools/static-nodes.c
> @@ -0,0 +1,246 @@
> +/*
> + * kmod-static-nodes - manage modules.devname
> + *
> + * Copyright (C) 2004-2012 Kay Sievers <kay@xxxxxxxx>
> + * Copyright (C) 2011-2013 ProFUSION embedded systems
> + * Copyright (C) 2013 Tom Gundersen <teg@xxxxxxx>
> + *
> + * 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.
> + *
> + * This program 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.
> + *
> + * You should have received a copy of the GNU General Public License
> + * along with this program. If not, see <http://www.gnu.org/licenses/>.
> + */
> +
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <stddef.h>
> +#include <getopt.h>
> +#include <errno.h>
> +#include <unistd.h>
> +#include <string.h>
> +#include <limits.h>
> +#include <sys/utsname.h>
> +#include <sys/stat.h>
> +#include <sys/types.h>
> +#include "libkmod-util.h"
> +
> +#include "kmod.h"
> +
> +struct static_nodes_format {
> + const char *name;
> + int (*write)(FILE *, char[], char[], char, unsigned int, unsigned int);
> + const char *description;
> +};
> +
> +static const struct static_nodes_format static_nodes_format_human;
> +static const struct static_nodes_format static_nodes_format_tmpfiles;
> +static const struct static_nodes_format static_nodes_format_devname;
> +
> +static const struct static_nodes_format *static_nodes_formats[] = {
> + &static_nodes_format_human,
> + &static_nodes_format_tmpfiles,
> + &static_nodes_format_devname,
> +};
> +
> +static const char cmdopts_s[] = "o:f:h";
> +static const struct option cmdopts[] = {
> + { "output", required_argument, 0, 'o'},
> + { "format", required_argument, 0, 'f'},
> + { "help", no_argument, 0, 'h'},
> + { },
> +};
> +
> +static int write_human(FILE *out, char modname[], char devname[], char type, unsigned int maj, unsigned int min)
> +{
> + int ret;
> +
> + ret = fprintf(out,
> + "Module: %s\n"
> + "\tDevice node: /dev/%s\n"
> + "\t\tType: %s device\n"
> + "\t\tMajor: %u\n"
> + "\t\tMinor: %u\n",
> + modname, devname, (type == 'c') ? "character" : "block", maj, min);
> + if (ret >= 0)
> + return EXIT_SUCCESS;
> + else
> + return EXIT_FAILURE;
> +}
> +
> +static const struct static_nodes_format static_nodes_format_human = {
> + .name = "human",
> + .write = write_human,
> + .description = "(default) a human readable format. Do not parse.",
> +};
> +
> +
> +static int write_tmpfiles(FILE *out, char modname[], char devname[], char type, unsigned int maj, unsigned int min)
> +{
> + int ret;
> +
> + ret = fprintf(out, "%c /dev/%s 0600 - - - %u:%u\n", type, devname, maj, min);
> + if (ret >= 0)
> + return EXIT_SUCCESS;
> + else
> + return EXIT_FAILURE;
> +}
> +
> +static const struct static_nodes_format static_nodes_format_tmpfiles = {
> + .name = "tmpfiles",
> + .write = write_tmpfiles,
> + .description = "the tmpfiles.d(5) format used by systemd-tmpfiles.",
> +};
> +
> +static int write_devname(FILE *out, char modname[], char devname[], char type, unsigned int maj, unsigned int min)
> +{
> + int ret;
> +
> + ret = fprintf(out, "%s %s %c%u:%u\n", modname, devname, type, maj, min);
> + if (ret >= 0)
> + return EXIT_SUCCESS;
> + else
> + return EXIT_FAILURE;
> +}
> +
> +static const struct static_nodes_format static_nodes_format_devname = {
> + .name = "devname",
> + .write = write_devname,
> + .description = "the modules.devname format.",
> +};
> +
> +static void help(void)
> +{
> + size_t i;
> +
> + printf("Usage:\n"
> + "\t%s static-nodes [options]\n"
> + "\n"
> + "kmod static-nodes outputs the static-node information of the currently running kernel.\n"
> + "\n"
> + "Options:\n"
> + "\t-f, --format=FORMAT use a machine-readable format\n"
> + "\t-o, --output=FILE write output to file\n"
> + "\t-h, --help show this help\n"
> + "\n"
> + "Formats:\n",
> + program_invocation_short_name);
> +
> + for (i = 0; i < ARRAY_SIZE(static_nodes_formats); i++) {
> + if (static_nodes_formats[i]->description != NULL) {
> + printf("\t%-12s %s\n", static_nodes_formats[i]->name,
> + static_nodes_formats[i]->description);
> + }
> + }
> +}
> +
> +static int do_static_nodes(int argc, char *argv[])
> +{
> + struct utsname kernel;
> + char modules[PATH_MAX];
> + FILE *in = NULL, *out = stdout;
> + const struct static_nodes_format *format = &static_nodes_format_human;
> + char buf[4096];
> + int ret = EXIT_SUCCESS;
> +
> + for (;;) {
> + int c, idx = 0, valid;
> + size_t i;
> +
> + c = getopt_long(argc, argv, cmdopts_s, cmdopts, &idx);
> + if (c == -1) {
> + break;
> + }
> + switch (c) {
> + case 'o':
> + out = fopen(optarg, "we");
> + if (out == NULL) {
> + fprintf(stderr, "Error: could not create %s!\n", optarg);
> + ret = EXIT_FAILURE;
> + goto finish;
> + }
> + break;
> + case 'f':
> + valid = 0;
> +
> + for (i = 0; i < ARRAY_SIZE(static_nodes_formats); i++) {
> + if (streq(static_nodes_formats[i]->name, optarg)) {
> + format = static_nodes_formats[i];
> + valid = 1;
> + }
> + }
> +
> + if (!valid) {
> + fprintf(stderr, "Unknown format: '%s'.\n", optarg);
> + help();
> + ret = EXIT_FAILURE;
> + goto finish;
> + }
> + break;
> + case 'h':
> + help();
> + goto finish;
> + case '?':
> + ret = EXIT_FAILURE;
> + goto finish;
> + default:
> + fprintf(stderr, "Unexpected commandline option '%c'.\n", c);
> + help();
> + ret = EXIT_FAILURE;
> + goto finish;
> + }
> + }
> +
> + if (uname(&kernel) < 0) {
> + fputs("Error: uname failed!\n", stderr);
> + ret = EXIT_FAILURE;
> + goto finish;
> + }
> + snprintf(modules, sizeof(modules), "/lib/modules/%s/modules.devname", kernel.release);
> + in = fopen(modules, "re");
> + if (in == NULL && errno != ENOENT) {
> + fprintf(stderr, "Error: could not open /lib/modules/%s/modules.devname!\n", kernel.release);
> + ret = EXIT_FAILURE;
> + goto finish;
> + }
> +
> + while (fgets(buf, sizeof(buf), in) != NULL) {
> + char modname[PATH_MAX];
> + char devname[PATH_MAX];
> + char type;
> + unsigned int maj, min;
> + int matches;
> +
> + if (buf[0] == '#')
> + continue;
> +
> + matches = sscanf(buf, "%s %s %c%u:%u", modname, devname, &type, &maj, &min);
> + if (matches != 5 || (type != 'c' && type != 'b')) {
> + fprintf(stderr, "Error: invalid devname entry: %s", buf);
> + ret = EXIT_FAILURE;
> + continue;
> + }
> +
> + format->write(out, modname, devname, type, maj, min);
> + }
> +
> +finish:
> + if (in)
> + fclose(in);
> + if (out)
> + fclose(out);
> + return ret;
> +}
> +
> +const struct kmod_cmd kmod_cmd_static_nodes = {
> + .name = "static-nodes",
> + .cmd = do_static_nodes,
> + .help = "outputs the static-node information installed with the currently running kernel",
> +};
> --
> 1.8.2.1
Patch has been applied.
After applying it I had to make a small fix. Please take a look on
279b177de62cd9778ed6b111a11d93d8e18fa169
Thanks
Lucas De Marchi
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