kernel: Support quoted values in cmdline arguments with new parser

This commit is contained in:
K. Lange 2023-10-09 20:01:42 +09:00
parent aebb75ac75
commit a679ef1b4c
5 changed files with 119 additions and 227 deletions

View File

@ -23,62 +23,7 @@
#include <unistd.h> #include <unistd.h>
#include <toaru/hashmap.h> #include <toaru/hashmap.h>
hashmap_t * args_map = NULL; #include "../kernel/misc/args.c"
int tokenize(char * str, char * sep, char **buf) {
char * pch_i;
char * save_i;
int argc = 0;
pch_i = strtok_r(str,sep,&save_i);
if (!pch_i) { return 0; }
while (pch_i != NULL) {
buf[argc] = (char *)pch_i;
++argc;
pch_i = strtok_r(NULL,sep,&save_i);
}
buf[argc] = NULL;
return argc;
}
void args_parse(char * _arg) {
char * arg = strdup(_arg);
char * argv[1024];
int argc = tokenize(arg, " ", argv);
for (int i = 0; i < argc; ++i) {
char * c = strdup(argv[i]);
char * name;
char * value;
name = c;
value = NULL;
/* Find the first = and replace it with a null */
char * v = c;
while (*v) {
if (*v == '=') {
*v = '\0';
v++;
value = v;
char * tmp = value;
/* scan it for \037 and replace with spaces */
while (*tmp) {
if (*tmp == '\037') {
*tmp = ' ';
}
tmp++;
}
goto _break;
}
v++;
}
_break:
hashmap_set(args_map, name, value);
}
free(arg);
}
void show_usage(int argc, char * argv[]) { void show_usage(int argc, char * argv[]) {
printf( printf(
@ -94,28 +39,15 @@ void show_usage(int argc, char * argv[]) {
} }
int main(int argc, char * argv[]) { int main(int argc, char * argv[]) {
/* Open */ char * cmdline = args_from_procfs();
FILE * f = fopen("/proc/cmdline", "r");
if (!f) return 1;
/* Read */
char * cmdline = malloc(4096); /* cmdline can't be longer than that */
memset(cmdline, 0, 4096);
size_t size = fread(cmdline, 1, 4096, f);
if (cmdline[size-1] == '\n') cmdline[size-1] = '\0';
fclose(f);
/* Parse */
args_map = hashmap_create(10);
args_parse(cmdline);
/* Figure out what we're doing */ /* Figure out what we're doing */
int opt; int opt;
while ((opt = getopt(argc, argv, "?g:q:s")) != -1) { while ((opt = getopt(argc, argv, "?g:q:s")) != -1) {
switch (opt) { switch (opt) {
case 'g': case 'g':
if (hashmap_has(args_map, optarg)) { if (hashmap_has(kernel_args_map, optarg)) {
char * tmp = (char*)hashmap_get(args_map, optarg); char * tmp = (char*)hashmap_get(kernel_args_map, optarg);
if (!tmp) { if (!tmp) {
printf("%s\n", optarg); /* special case = present but not set should yield name of variable */ printf("%s\n", optarg); /* special case = present but not set should yield name of variable */
} else { } else {
@ -126,9 +58,9 @@ int main(int argc, char * argv[]) {
return 1; return 1;
} }
case 'q': case 'q':
return !hashmap_has(args_map,optarg); return !hashmap_has(kernel_args_map,optarg);
case 's': case 's':
return size; return strlen(cmdline);
case '?': case '?':
show_usage(argc, argv); show_usage(argc, argv);
return 1; return 1;

View File

@ -37,21 +37,6 @@
static int _debug = 0; static int _debug = 0;
static FILE * _splash = NULL; static FILE * _splash = NULL;
int tokenize(char * str, char * sep, char **buf) {
char * pch_i;
char * save_i;
int argc = 0;
pch_i = strtok_r(str,sep,&save_i);
if (!pch_i) { return 0; }
while (pch_i != NULL) {
buf[argc] = (char *)pch_i;
++argc;
pch_i = strtok_r(NULL,sep,&save_i);
}
buf[argc] = NULL;
return argc;
}
void copy_link(char * source, char * dest, int mode, int uid, int gid) { void copy_link(char * source, char * dest, int mode, int uid, int gid) {
//fprintf(stderr, "need to copy link %s to %s\n", source, dest); //fprintf(stderr, "need to copy link %s to %s\n", source, dest);
char tmp[1024]; char tmp[1024];
@ -144,51 +129,11 @@ void free_ramdisk(char * path) {
close(fd); close(fd);
} }
hashmap_t * get_cmdline(void) { #include "../kernel/misc/args.c"
int fd = open("/proc/cmdline", O_RDONLY); static hashmap_t * get_cmdline(void) {
char * out = malloc(1024); char * results = args_from_procfs();
size_t r = read(fd, out, 1024); if (results) free(results);
out[r] = '\0'; return kernel_args_map;
if (out[r-1] == '\n') {
out[r-1] = '\0';
}
char * arg = strdup(out);
char * argv[1024];
int argc = tokenize(arg, " ", argv);
/* New let's parse the tokens into the arguments list so we can index by key */
hashmap_t * args = hashmap_create(10);
for (int i = 0; i < argc; ++i) {
char * c = strdup(argv[i]);
char * name;
char * value;
name = c;
value = NULL;
/* Find the first = and replace it with a null */
char * v = c;
while (*v) {
if (*v == '=') {
*v = '\0';
v++;
value = v;
goto _break;
}
v++;
}
_break:
hashmap_set(args, name, value);
}
free(arg);
free(out);
return args;
} }
int main(int argc, char * argv[]) { int main(int argc, char * argv[]) {

View File

@ -67,69 +67,13 @@ static void say_hello(void) {
update_message(hello_msg); update_message(hello_msg);
} }
static int tokenize(char * str, char * sep, char **buf) { #include "../kernel/misc/args.c"
char * pch_i;
char * save_i;
int argc = 0;
pch_i = strtok_r(str,sep,&save_i);
if (!pch_i) { return 0; }
while (pch_i != NULL) {
buf[argc] = (char *)pch_i;
++argc;
pch_i = strtok_r(NULL,sep,&save_i);
}
buf[argc] = NULL;
return argc;
}
static hashmap_t * get_cmdline(void) { static hashmap_t * get_cmdline(void) {
int fd = open("/proc/cmdline", O_RDONLY); char * results = args_from_procfs();
char * out = malloc(1024); if (results) free(results);
size_t r = read(fd, out, 1024); return kernel_args_map;
out[r] = '\0';
if (out[r-1] == '\n') {
out[r-1] = '\0';
} }
char * arg = strdup(out);
char * argv[1024];
int argc = tokenize(arg, " ", argv);
/* New let's parse the tokens into the arguments list so we can index by key */
hashmap_t * args = hashmap_create(10);
for (int i = 0; i < argc; ++i) {
char * c = strdup(argv[i]);
char * name;
char * value;
name = c;
value = NULL;
/* Find the first = and replace it with a null */
char * v = c;
while (*v) {
if (*v == '=') {
*v = '\0';
v++;
value = v;
goto _break;
}
v++;
}
_break:
hashmap_set(args, name, value);
}
free(arg);
free(out);
return args;
}
int main(int argc, char * argv[]) { int main(int argc, char * argv[]) {
if (getuid() != 0) { if (getuid() != 0) {
fprintf(stderr, "%s: only root should run this\n", argv[0]); fprintf(stderr, "%s: only root should run this\n", argv[0]);

View File

@ -39,7 +39,7 @@ char * LINK_TEXT = "https://toaruos.org - https://github.com/klange/toaruos";
/* Boot command line strings */ /* Boot command line strings */
#define DEFAULT_ROOT_CMDLINE "root=/dev/ram0 " #define DEFAULT_ROOT_CMDLINE "root=/dev/ram0 "
#define DEFAULT_GRAPHICAL_CMDLINE "start=live-session " #define DEFAULT_GRAPHICAL_CMDLINE "start=live-session "
#define DEFAULT_SINGLE_CMDLINE "start=terminal\037-F " #define DEFAULT_SINGLE_CMDLINE "start=\"terminal -F\" "
#define DEFAULT_TEXT_CMDLINE "start=--vga vid=text " #define DEFAULT_TEXT_CMDLINE "start=--vga vid=text "
#define DEFAULT_VID_CMDLINE "vid=auto " #define DEFAULT_VID_CMDLINE "vid=auto "
#define MIGRATE_CMDLINE "migrate " #define MIGRATE_CMDLINE "migrate "

View File

@ -6,14 +6,34 @@
* hard disk partition should be mounted as root. We parse them * hard disk partition should be mounted as root. We parse them
* into a hash table for easy lookup by key. * into a hash table for easy lookup by key.
* *
* An argument may be value-less (having no '='), in which case
* its value in the hash table will be NULL but it will be present.
* Examples of value-less arguments are @c lfbwc or @c noi965.
*
* Arguments with values can have quoted or unquoted values. Unquoted
* values are terminated by a space or the end of the command line and
* are not processed for escapes. Examples of arguments with
* unquoted values are @c root=/dev/ram0 or @c start=live-session.
*
* Quoted values must started immediately with a double quote (").
* Double quotes within the value may be escaped with a backslash (\).
* Backslash can also be escaped. Any other character after a
* backslash results in both a literal backslash and the following
* character.
*
* If a quoted value is not properly terminated with an unescaped
* double quote character, the entire argument will be ignored.
*
* @copyright This file is part of ToaruOS and is released under the terms * @copyright This file is part of ToaruOS and is released under the terms
* of the NCSA / University of Illinois License - see LICENSE.md * of the NCSA / University of Illinois License - see LICENSE.md
* Copyright (C) 2011-2021 K. Lange * Copyright (C) 2011-2023 K. Lange
*/ */
#ifdef _KERNEL_
# include <kernel/string.h> # include <kernel/string.h>
# include <kernel/args.h> # include <kernel/args.h>
# include <kernel/tokenize.h> # include <kernel/tokenize.h>
# include <kernel/hashmap.h> # include <kernel/hashmap.h>
#endif
hashmap_t * kernel_args_map = NULL; hashmap_t * kernel_args_map = NULL;
@ -43,43 +63,94 @@ char * args_value(const char * karg) {
* *
* @param arg A string containing all arguments, separated by spaces. * @param arg A string containing all arguments, separated by spaces.
*/ */
void args_parse(const char * _arg) { void args_parse(const char * cmdline) {
/* Sanity check... */ /* Sanity check... */
if (!_arg) { return; } if (!cmdline) { return; }
if (!kernel_args_map) { kernel_args_map = hashmap_create(10); }
char * argbuf = strdup(cmdline);
char * x = argbuf;
char * arg = strdup(_arg); for (;;) {
char * argv[1024]; while (*x && *x == ' ') x++; /* skip spaces */
int argc = tokenize(arg, " ", argv); if (!*x) break;
/* New let's parse the tokens into the arguments list so we can index by key */ char * value = NULL;
if (!kernel_args_map) { char * key = x;
while (*x && *x != '=' && *x != ' ') x++;
if (*x == '=') {
*x++ = '\0';
if (*x == '"') {
/* Start of quoted value */
x++;
value = x;
char * w = x;
while (*x && *x != '"') {
if (*x == '\\') {
x++;
switch (*x) {
case '"': *w++ = '"'; x++; break;
case '\\': *w++ = '\\'; x++; break;
case '\0': goto _parse_error;
default: *w++ = '\\'; *w++ = *x++; break;
}
} else {
*w++ = *x++;
}
}
if (*x == '"') {
*w = '\0';
x++;
} else if (*x == '\0') {
goto _parse_error;
}
} else {
/* Start of unquoted value */
value = x;
while (*x && *x != ' ') x++;
if (*x == ' ') {
*x = '\0';
x++;
}
}
} else if (*x == ' ') {
/* Value-less argument where we need to set nil byte */
*x++ = '\0';
}
hashmap_set(kernel_args_map, key, value ? strdup(value) : NULL);
}
_parse_error:
free(argbuf);
return;
}
#ifndef _KERNEL_
char * args_from_procfs(void) {
/* Open */
FILE * f = fopen("/proc/cmdline", "r");
if (!f) return NULL;
/* Determine size */
fseek(f, 0, SEEK_END);
size_t size = ftell(f);
fseek(f, 0, SEEK_SET);
/* Read */
char * cmdline = calloc(size + 1, 1);
size_t rsize = fread(cmdline, 1, size, f);
if (cmdline[rsize-1] == '\n') cmdline[rsize-1] = '\0';
fclose(f);
/* Parse */
kernel_args_map = hashmap_create(10); kernel_args_map = hashmap_create(10);
args_parse(cmdline);
return cmdline;
} }
for (int i = 0; i < argc; ++i) { #endif
char * c = strdup(argv[i]);
char * name;
char * value;
name = c;
value = NULL;
/* Find the first = and replace it with a null */
char * v = c;
while (*v) {
if (*v == '=') {
*v = '\0';
v++;
value = v;
goto _break;
}
v++;
}
_break:
hashmap_set(kernel_args_map, name, value);
}
free(arg);
}