diff options
Diffstat (limited to 'src/run-generator')
-rw-r--r-- | src/run-generator/run-generator.c | 138 |
1 files changed, 138 insertions, 0 deletions
diff --git a/src/run-generator/run-generator.c b/src/run-generator/run-generator.c new file mode 100644 index 0000000..e3fb7f2 --- /dev/null +++ b/src/run-generator/run-generator.c @@ -0,0 +1,138 @@ +/* SPDX-License-Identifier: LGPL-2.1-or-later */ + +#include <unistd.h> + +#include "alloc-util.h" +#include "escape.h" +#include "fd-util.h" +#include "fileio.h" +#include "generator.h" +#include "glyph-util.h" +#include "mkdir.h" +#include "proc-cmdline.h" +#include "special.h" +#include "specifier.h" +#include "strv.h" + +static const char *arg_dest = NULL; +static char **arg_commands = NULL; +static char *arg_success_action = NULL; +static char *arg_failure_action = NULL; + +STATIC_DESTRUCTOR_REGISTER(arg_commands, strv_freep); +STATIC_DESTRUCTOR_REGISTER(arg_success_action, freep); +STATIC_DESTRUCTOR_REGISTER(arg_failure_action, freep); + +static int parse(const char *key, const char *value, void *data) { + int r; + + if (proc_cmdline_key_streq(key, "systemd.run")) { + + if (proc_cmdline_value_missing(key, value)) + return 0; + + r = strv_extend(&arg_commands, value); + if (r < 0) + return log_oom(); + + } else if (proc_cmdline_key_streq(key, "systemd.run_success_action")) { + + if (proc_cmdline_value_missing(key, value)) + return 0; + + return free_and_strdup_warn(&arg_success_action, value); + + } else if (proc_cmdline_key_streq(key, "systemd.run_failure_action")) { + + if (proc_cmdline_value_missing(key, value)) + return 0; + + return free_and_strdup_warn(&arg_failure_action, value); + } + + return 0; +} + +static int generate(void) { + _cleanup_fclose_ FILE *f = NULL; + const char *p; + int r; + + if (strv_isempty(arg_commands) && !arg_success_action) + return 0; + + p = strjoina(arg_dest, "/kernel-command-line.service"); + f = fopen(p, "wxe"); + if (!f) + return log_error_errno(errno, "Failed to create unit file %s: %m", p); + + fputs("# Automatically generated by systemd-run-generator\n\n" + "[Unit]\n" + "Description=Command from Kernel Command Line\n" + "Documentation=man:systemd-run-generator(8)\n" + "SourcePath=/proc/cmdline\n", f); + + if (!streq_ptr(arg_success_action, "none")) + fprintf(f, "SuccessAction=%s\n", + arg_success_action ?: "exit"); + + if (!streq_ptr(arg_failure_action, "none")) + fprintf(f, "FailureAction=%s\n", + arg_failure_action ?: "exit"); + + fputs("\n" + "[Service]\n" + "Type=oneshot\n" + "StandardOutput=journal+console\n", f); + + STRV_FOREACH(c, arg_commands) { + _cleanup_free_ char *a = NULL; + + a = specifier_escape(*c); + if (!a) + return log_oom(); + + fprintf(f, "ExecStart=%s\n", a); + } + + r = fflush_and_check(f); + if (r < 0) + return log_error_errno(r, "Failed to write unit file %s: %m", p); + + /* Let's create a target we can link "default.target" to */ + p = strjoina(arg_dest, "/kernel-command-line.target"); + r = write_string_file( + p, + "# Automatically generated by systemd-run-generator\n\n" + "[Unit]\n" + "Description=Command from Kernel Command Line\n" + "Documentation=man:systemd-run-generator(8)\n" + "SourcePath=/proc/cmdline\n" + "Requires=kernel-command-line.service\n" + "After=kernel-command-line.service\n", + WRITE_STRING_FILE_CREATE|WRITE_STRING_FILE_NOFOLLOW); + if (r < 0) + return log_error_errno(r, "Failed to create unit file %s: %m", p); + + /* And now redirect default.target to our new target */ + p = strjoina(arg_dest, "/" SPECIAL_DEFAULT_TARGET); + if (symlink("kernel-command-line.target", p) < 0) + return log_error_errno(errno, "Failed to link unit file kernel-command-line.target %s %s: %m", + special_glyph(SPECIAL_GLYPH_ARROW_RIGHT), p); + + return 0; +} + +static int run(const char *dest, const char *dest_early, const char *dest_late) { + int r; + + assert_se(arg_dest = dest); + + r = proc_cmdline_parse(parse, NULL, PROC_CMDLINE_RD_STRICT|PROC_CMDLINE_STRIP_RD_PREFIX); + if (r < 0) + log_warning_errno(r, "Failed to parse kernel command line, ignoring: %m"); + + return generate(); +} + +DEFINE_MAIN_GENERATOR_FUNCTION(run); |