minecraft-pi-docker/launcher/src/bootstrap.c

350 lines
10 KiB
C

#define _FILE_OFFSET_BITS 64
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <dirent.h>
#include <errno.h>
#include <sys/stat.h>
#include <libreborn/libreborn.h>
#include "bootstrap.h"
#include "ldconfig.h"
// Set Environmental Variable
#define PRESERVE_ENVIRONMENTAL_VARIABLE(name) \
{ \
char *original_env_value = getenv(name); \
if (original_env_value != NULL) { \
setenv("ORIGINAL_" name, original_env_value, 1); \
} \
}
static void trim(char **value) {
// Remove Trailing Colon
int length = strlen(*value);
if ((*value)[length - 1] == ':') {
(*value)[length - 1] = '\0';
}
if ((*value)[0] == ':') {
*value = &(*value)[1];
}
}
void set_and_print_env(const char *name, char *value) {
// Set Variable With No Trailing Colon
static const char *unmodified_name_prefix = "MCPI_";
if (strncmp(unmodified_name_prefix, name, strlen(unmodified_name_prefix)) != 0) {
trim(&value);
}
// Print New Value
DEBUG("Set %s = %s", name, value);
// Set The Value
setenv(name, value, 1);
}
#ifndef __ARM_ARCH
#define PASS_ENVIRONMENTAL_VARIABLE_TO_QEMU(name) \
{ \
char *old_value = getenv("QEMU_SET_ENV"); \
char *new_value = NULL; \
/* Pass Variable */ \
safe_asprintf(&new_value, "%s%s%s=%s", old_value == NULL ? "" : old_value, old_value == NULL ? "" : ",", name, getenv(name)); \
setenv("QEMU_SET_ENV", new_value, 1); \
free(new_value); \
/* Reset Variable */ \
RESET_ENVIRONMENTAL_VARIABLE(name); \
}
#endif
// Get Environmental Variable
static char *get_env_safe(const char *name) {
// Get Variable Or Blank String If Not Set
char *ret = getenv(name);
return ret != NULL ? ret : "";
}
// Get All Mods In Folder
static void load(char **ld_preload, char *folder) {
int folder_name_length = strlen(folder);
// Retry Until Successful
while (1) {
// Open Folder
DIR *dp = opendir(folder);
if (dp != NULL) {
// Loop Through Folder
struct dirent *entry = NULL;
errno = 0;
while (1) {
errno = 0;
entry = readdir(dp);
if (entry != NULL) {
// Check If File Is Regular
if (entry->d_type == DT_REG) {
// Get Full Name
int name_length = strlen(entry->d_name);
int total_length = folder_name_length + name_length;
char name[total_length + 1];
// Concatenate Folder Name And File Name
for (int i = 0; i < folder_name_length; i++) {
name[i] = folder[i];
}
for (int i = 0; i < name_length; i++) {
name[folder_name_length + i] = entry->d_name[i];
}
// Add Terminator
name[total_length] = '\0';
// Check If File Is Executable
int result = access(name, R_OK);
if (result == 0) {
// Add To LD_PRELOAD
string_append(ld_preload, ":%s", name);
} else if (result == -1 && errno != 0) {
// Fail
INFO("Unable To Acesss: %s: %s", name, strerror(errno));
errno = 0;
}
}
} else if (errno != 0) {
// Error Reading Contents Of Folder
ERR("Error Reading Directory: %s: %s", folder, strerror(errno));
} else {
// Done!
break;
}
}
// Close Folder
closedir(dp);
// Exit Function
return;
} else if (errno == ENOENT) {
// Folder Doesn't Exists, Attempt Creation
int ret = mkdir(folder, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH);
if (ret != 0) {
// Unable To Create Folder
ERR("Error Creating Directory: %s: %s", folder, strerror(errno));
}
// Continue Retrying
} else {
// Unable To Open Folder
ERR("Error Opening Directory: %s: %s", folder, strerror(errno));
}
}
}
#define MCPI_BINARY "minecraft-pi"
#define QEMU_BINARY "qemu-arm"
// Pre-Bootstrap
void pre_bootstrap() {
// AppImage
#ifdef MCPI_IS_APPIMAGE_BUILD
char *owd = getenv("OWD");
if (owd != NULL && chdir(owd) != 0) {
ERR("AppImage: Unable To Fix Current Directory: %s", strerror(errno));
}
#endif
// Get Binary Directory
char *binary_directory = get_binary_directory();
// Configure PATH
{
// Add Library Directory
char *new_path;
safe_asprintf(&new_path, "%s/bin", binary_directory);
// Add Existing PATH
{
char *value = get_env_safe("PATH");
if (strlen(value) > 0) {
string_append(&new_path, ":%s", value);
}
}
// Set And Free
set_and_print_env("PATH", new_path);
free(new_path);
}
// Free Binary Directory
free(binary_directory);
}
// Bootstrap
void bootstrap(int argc, char *argv[]) {
INFO("%s", "Configuring Game...");
// Get Binary Directory
char *binary_directory = get_binary_directory();
// Handle AppImage
char *usr_prefix = NULL;
#ifdef MCPI_IS_APPIMAGE_BUILD
usr_prefix = getenv("APPDIR");
#endif
if (usr_prefix == NULL) {
usr_prefix = "";
}
// Configure LD_LIBRARY_PATH
{
// Preserve
PRESERVE_ENVIRONMENTAL_VARIABLE("LD_LIBRARY_PATH");
char *new_ld_path = NULL;
// Add Library Directory
safe_asprintf(&new_ld_path, "%s/lib", binary_directory);
// Add MCPI_LD_LIBRARY_PATH
{
char *value = get_env_safe("MCPI_LD_LIBRARY_PATH");
if (strlen(value) > 0) {
string_append(&new_ld_path, ":%s", value);
}
}
// Add LD_LIBRARY_PATH (ARM32 Only)
#ifdef __arm__
{
char *value = get_env_safe("LD_LIBRARY_PATH");
if (strlen(value) > 0) {
string_append(&new_ld_path, ":%s", value);
}
}
#endif
// Load ARM Libraries (Ensure Priority)
string_append(&new_ld_path, ":%s/usr/lib/arm-linux-gnueabihf:%s/usr/arm-linux-gnueabihf/lib", usr_prefix, usr_prefix);
// Add Full Library Search Path
{
char *value = get_full_library_search_path();
if (strlen(value) > 0) {
string_append(&new_ld_path, ":%s", value);
}
free(value);
}
// Add Fallback Library Directory
string_append(&new_ld_path, ":%s/fallback-lib", binary_directory);
// Set And Free
set_and_print_env("LD_LIBRARY_PATH", new_ld_path);
free(new_ld_path);
}
// Configure LD_PRELOAD
{
// Preserve
PRESERVE_ENVIRONMENTAL_VARIABLE("LD_PRELOAD");
char *new_ld_preload = NULL;
// Built-In Mods
{
// Get Mods Folder
char *mods_folder = NULL;
safe_asprintf(&mods_folder, "%s/mods/", binary_directory);
// Load Mods From ./mods
load(&new_ld_preload, mods_folder);
// Free Mods Folder
free(mods_folder);
}
// ~/.minecraft-pi/mods
{
// Get Mods Folder
char *mods_folder = NULL;
safe_asprintf(&mods_folder, "%s" HOME_SUBDIRECTORY_FOR_GAME_DATA "/mods/", getenv("HOME"));
// Load Mods From ./mods
load(&new_ld_preload, mods_folder);
// Free Mods Folder
free(mods_folder);
}
// Add MCPI_LD_PRELOAD
{
char *value = get_env_safe("MCPI_LD_PRELOAD");
if (strlen(value) > 0) {
string_append(&new_ld_preload, ":%s", value);
}
}
// Add LD_PRELOAD (ARM32 Only)
#ifdef __arm__
{
char *value = get_env_safe("MCPI_LD_PRELOAD");
if (strlen(value) > 0) {
string_append(&new_ld_preload, ":%s", value);
}
}
#endif
// Set LD_PRELOAD
set_and_print_env("LD_PRELOAD", new_ld_preload);
free(new_ld_preload);
}
// Resolve Binary Path & Set MCPI_DIRECTORY
{
// Resolve Full Binary Path
char *full_path = NULL;
safe_asprintf(&full_path, "%s/" MCPI_BINARY, binary_directory);
char *resolved_path = realpath(full_path, NULL);
ALLOC_CHECK(resolved_path);
free(full_path);
// Set MCPI_EXECUTABLE_PATH
set_and_print_env("MCPI_EXECUTABLE_PATH", resolved_path);
// Set MCPI_DIRECTORY
chop_last_component(&resolved_path);
set_and_print_env("MCPI_DIRECTORY", resolved_path);
free(resolved_path);
}
// Free Binary Directory
free(binary_directory);
// Start Game
INFO("%s", "Starting Game...");
// Arguments
int argv_start = 2; // argv = &new_args[argv_start]
char *new_args[argv_start /* 2 Potential Prefix Arguments (QEMU And Linker) */ + argc + 1 /* NULL-Terminator */]; //
// Copy Existing Arguments
for (int i = 1; i < argc; i++) {
new_args[i + argv_start] = argv[i];
}
// NULL-Terminator
new_args[argv_start + argc] = NULL;
// Set Executable Argument
new_args[argv_start] = getenv("MCPI_EXECUTABLE_PATH");
// Non-ARM32 Systems Need Manually Specified Linker
#ifndef __arm__
argv_start--;
char *linker = NULL;
safe_asprintf(&linker, "%s/usr/arm-linux-gnueabihf/lib/ld-linux-armhf.so.3", usr_prefix);
new_args[argv_start] = linker;
// Non-ARM Systems Need QEMU
#ifndef __ARM_ARCH
argv_start--;
new_args[argv_start] = QEMU_BINARY;
// Prevent QEMU From Being Modded
PASS_ENVIRONMENTAL_VARIABLE_TO_QEMU("LD_LIBRARY_PATH");
PASS_ENVIRONMENTAL_VARIABLE_TO_QEMU("LD_PRELOAD");
#endif
#endif
// Run
char **new_argv = &new_args[argv_start];
safe_execvpe(new_argv[0], new_argv, environ);
}