Add service(8) config support.

This commit is contained in:
Jonas 'Sortie' Termansen 2024-05-09 12:49:42 +00:00
parent 4e72a157fa
commit 818f4c4ecd
1 changed files with 251 additions and 2 deletions

View File

@ -18,9 +18,12 @@
*/
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/un.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <getopt.h>
#include <stdbool.h>
#include <stddef.h>
@ -29,6 +32,141 @@
#include <stdio.h>
#include <unistd.h>
static bool array_add(void*** array_ptr,
size_t* used_ptr,
size_t* length_ptr,
void* value)
{
void** array;
memcpy(&array, array_ptr, sizeof(array)); // Strict aliasing.
if ( *used_ptr == *length_ptr )
{
size_t length = *length_ptr;
if ( !length )
length = 4;
void** new_array = reallocarray(array, length, 2 * sizeof(void*));
if ( !new_array )
return false;
array = new_array;
memcpy(array_ptr, &array, sizeof(array)); // Strict aliasing.
*length_ptr = length * 2;
}
memcpy(array + (*used_ptr)++, &value, sizeof(value)); // Strict aliasing.
return true;
}
static char** tokenize(size_t* out_tokens_used, const char* string)
{
size_t tokens_used = 0;
size_t tokens_length = 0;
char** tokens = malloc(sizeof(char*));
if ( !tokens )
return NULL;
bool failed = false;
bool invalid = false;
while ( *string )
{
if ( isspace((unsigned char) *string) )
{
string++;
continue;
}
if ( *string == '#' )
break;
char* token;
size_t token_size;
FILE* fp = open_memstream(&token, &token_size);
if ( !fp )
{
failed = true;
break;
}
bool singly = false;
bool doubly = false;
bool escaped = false;
for ( char c = *string++; c; c = *string++ )
{
if ( !escaped && !singly && !doubly && isspace((unsigned char) c) )
break;
if ( !escaped && !doubly && c == '\'' )
{
singly = !singly;
continue;
}
if ( !escaped && !singly && c == '"' )
{
doubly = !doubly;
continue;
}
if ( !singly && !escaped && c == '\\' )
{
escaped = true;
continue;
}
if ( escaped )
{
switch ( c )
{
case 'a': c = '\a'; break;
case 'b': c = '\b'; break;
case 'e': c = '\e'; break;
case 'f': c = '\f'; break;
case 'n': c = '\n'; break;
case 'r': c = '\r'; break;
case 't': c = '\t'; break;
case 'v': c = '\v'; break;
default: break;
};
}
escaped = false;
if ( fputc((unsigned char) c, fp) == EOF )
{
failed = true;
break;
}
}
if ( singly || doubly || escaped )
{
fclose(fp);
free(token);
invalid = true;
break;
}
if ( fflush(fp) == EOF )
{
fclose(fp);
free(token);
failed = true;
break;
}
fclose(fp);
if ( !array_add((void***) &tokens, &tokens_used, &tokens_length,
token) )
{
free(token);
failed = true;
break;
}
}
if ( failed || invalid )
{
for ( size_t i = 0; i < tokens_used; i++ )
free(tokens[i]);
free(tokens);
if ( invalid )
errno = 0;
return NULL;
}
char** new_tokens = reallocarray(tokens, tokens_used, sizeof(char*));
if ( new_tokens )
tokens = new_tokens;
*out_tokens_used = tokens_used;
return tokens;
}
static int open_local_client_socket(const char* path, int flags)
{
size_t path_length = strlen(path);
@ -47,17 +185,115 @@ static int open_local_client_socket(const char* path, int flags)
return fd;
}
static void rewrite(const char* path, const char* daemon, const char* flags)
{
FILE* fp = fopen(path, "r");
if ( !fp )
{
if ( errno != ENOENT )
err(1, "%s", path);
}
char* out_path;
if ( asprintf(&out_path, "%s.XXXXXX", path) < 0 )
err(1, "malloc");
int out_fd = mkstemp(out_path);
if ( out_fd < 0 )
err(1, "mkstemp: %s.XXXXXX", path);
FILE* out = fdopen(out_fd, "w");
if ( !out )
{
unlink(out_path);
err(1, "fdopen");
}
bool found = false;
char* line = NULL;
size_t line_size = 0;
ssize_t line_length;
off_t line_number = 0;
while ( fp && 0 < (line_length = getline(&line, &line_size, fp)) )
{
line_number++;
size_t tokenc;
char** tokens = tokenize(&tokenc, line);
if ( !tokens )
{
unlink(out_path);
if ( errno )
err(1, "%s", path);
else
errx(1, "%s:%ji: Syntax error", path, (intmax_t) line_number);
}
if ( 2 <= tokenc &&
!strcmp(tokens[0], "require") && !strcmp(tokens[1], daemon) )
{
found = true;
if ( flags )
fprintf(out, "require %s%s\n", daemon, flags);
}
else
fputs(line, out);
}
free(line);
if ( !found && flags )
fprintf(out, "require %s%s\n", daemon, flags);
if ( (fp && ferror(fp)) || ferror(out) || fflush(out) == EOF )
{
unlink(out_path);
err(1, "%s", path);
}
if ( fp )
{
struct stat st;
fstat(fileno(fp), &st);
fchmod(out_fd, st.st_mode & 07777);
fchown(out_fd, st.st_uid, st.st_gid);
fclose(fp);
}
else
fchmod(out_fd, 0666 & ~getumask());
if ( rename(out_path, path) < 0 )
{
unlink(out_path);
err(1, "rename: %s -> %s", out_path, path);
}
fclose(out);
}
static bool check_daemon_exists_in_dir(const char* dir, const char* daemon)
{
char* path;
if ( asprintf(&path, "%s/%s", dir, daemon) < 0 )
err(1, "malloc");
bool result = !access(path, F_OK);
free(path);
return result;
}
static void check_daemon_exists(const char* daemon)
{
if ( !check_daemon_exists_in_dir("/etc/init", daemon) &&
!check_daemon_exists_in_dir("/share/init", daemon) )
errx(1, "%s: Daemon does not exist", daemon);
}
int main(int argc, char* argv[])
{
const char* init_socket = getenv("INIT_SOCKET");
if ( !init_socket )
init_socket = "/var/run/init";
bool exit_code = false;
bool no_await = false;
bool optional = true;
bool raw = false;
const char* source = "local";
const struct option longopts[] =
{
{"exit-code", no_argument, NULL, 256},
{"no-await", no_argument, NULL, 257},
{"no-optional", no_argument, NULL, 258},
{"source", required_argument, NULL, 't'},
{"raw", no_argument, NULL, 'r'},
{0, 0, 0, 0}
@ -70,6 +306,9 @@ int main(int argc, char* argv[])
{
case 'r': raw = true; break;
case 's': source = optarg; break;
case 256: exit_code = true; break;
case 257: no_await = true; break;
case 258: optional = false; break;
default: return 2;
}
}
@ -94,15 +333,25 @@ int main(int argc, char* argv[])
const char* daemon = argv[optind++];
const char* command = argv[optind++];
char flags[sizeof(" optional no-await exit-code")];
snprintf(flags, sizeof(flags), "%s%s%s",
optional ? " optional" : "",
no_await ? " no-await" : "",
exit_code ? " exit-code" : "");
char* source_path;
if ( asprintf(&source_path, "/etc/init/%s", source) < 0 )
err(1, "malloc");
if ( !strcmp(command, "enable") )
{
// TODO: Write out new config.
check_daemon_exists(daemon);
rewrite(source_path, daemon, flags);
if ( dprintf(fd, "require %s %s start\n", source, daemon) < 0 )
err(1, "%s", init_socket);
}
else if ( !strcmp(command, "disable") )
{
// TODO: Write out new config.
rewrite(source_path, daemon, NULL);
if ( dprintf(fd, "unrequire %s %s\n", source, daemon) < 0 )
err(1, "%s", init_socket);
}