Emulation for kernel module handling in userland.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@2276 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Ingo Weinhold 2002-12-21 19:11:24 +00:00
parent 6ddccb275f
commit 739b4f1491

View File

@ -0,0 +1,484 @@
// kernelland_emu.cpp
#include <set>
#include <stdio.h>
#include <string>
#include <Autolock.h>
#include <Directory.h>
#include <Entry.h>
#include <KernelExport.h>
#include <module.h>
#include <List.h>
#include <Locker.h>
#include <Path.h>
#define TRACE(x)
//#define TRACE(x) printf x
static const char *gModuleDirs[] = {
"distro/x86.R1/beos/system/add-ons/userland",
NULL
};
struct module_name_list {
set<string> names;
set<string>::iterator it;
};
// Module
class Module {
public:
Module();
~Module();
status_t Init(const char *name, bool isPath = false);
void Unset();
void Get();
bool Put();
module_info *Info() const { return fInfo; }
private:
bool _Load(const char *path, const char *name, bool isPath);
private:
image_id fAddOn;
module_info *fInfo;
int32 fReferenceCount;
bool fInitialized;
};
// constructor
Module::Module()
: fAddOn(-1),
fInfo(NULL),
fReferenceCount(0),
fInitialized(false)
{
}
// constructor
Module::~Module()
{
Unset();
}
// Init
status_t
Module::Init(const char *name, bool isPath)
{
TRACE(("Module::Init(): searching module `%s'...\n", name));
Unset();
status_t error = (name ? B_OK : B_BAD_VALUE);
if (error == B_OK) {
error = B_ENTRY_NOT_FOUND;
if (isPath) {
// name is a path name: try to load it
if (_Load(name, name, isPath))
error = B_OK;
} else {
// name is a relative module name: search in the module dirs
for (int32 i = 0; gModuleDirs[i]; i++) {
TRACE(("Module::Init(): ...in `%s'\n", gModuleDirs[i]));
BPath path;
if (path.SetTo(gModuleDirs[i]) == B_OK
&& path.SetTo(path.Path(), name) == B_OK) {
if (_Load(path.Path(), name, isPath)) {
error = B_OK;
break;
}
}
}
}
}
return error;
}
// Unset
void
Module::Unset()
{
if (fAddOn >= 0) {
if (fInfo)
fInfo->std_ops(B_MODULE_UNINIT);
unload_add_on(fAddOn);
}
fAddOn = -1;
fInfo = NULL;
fReferenceCount = 0;
fInitialized = false;
}
// Get
void
Module::Get()
{
if (fAddOn >= 0)
fReferenceCount++;
}
// Put
bool
Module::Put()
{
if (fAddOn >= 0)
fReferenceCount--;
return (fReferenceCount == 0 && !(fInfo->flags & B_KEEP_LOADED));
}
// _Load
bool
Module::_Load(const char *path, const char *name, bool isPath)
{
TRACE(("Module::_Load(): trying to load `%s'\n", path));
BEntry entry;
if (entry.SetTo(path) == B_OK && entry.Exists()) {
image_id image = load_add_on(path);
module_info **infos = NULL;
if (image >= 0
&& get_image_symbol(image, "modules", B_SYMBOL_TYPE_DATA,
(void**)&infos) == B_OK
&& infos != NULL) {
for (int32 i = 0; module_info *info = infos[i]; i++) {
if ((isPath || !strcmp(name, info->name))
&& info->std_ops(B_MODULE_INIT) == B_OK) {
fAddOn = image;
fInfo = info;
fReferenceCount = 0;
return true;
}
}
}
} else if (!isPath) {
// entry does not exist -- try loading the parent path
BPath parentPath;
if (BPath(path).GetParent(&parentPath) == B_OK)
return _Load(parentPath.Path(), name, isPath);
}
return false;
}
// ModuleList
class ModuleList : public BLocker {
public:
ModuleList();
~ModuleList();
int32 CountModules() const;
Module *ModuleAt(int32 index) const;
bool AddModule(Module *module);
bool RemoveModule(Module *module);
Module *FindModule(const char *path);
private:
BList fModules;
};
// constructor
ModuleList::ModuleList()
{
}
// destructor
ModuleList::~ModuleList()
{
}
// CountModules
int32
ModuleList::CountModules() const
{
return fModules.CountItems();
}
// ModuleAt
Module *
ModuleList::ModuleAt(int32 index) const
{
return (Module*)fModules.ItemAt(index);
}
// AddModule
bool
ModuleList::AddModule(Module *module)
{
bool result = false;
if (module && !FindModule(module->Info()->name))
result = fModules.AddItem(module);
return module;
}
// RemoveModule
bool
ModuleList::RemoveModule(Module *module)
{
return (module && fModules.RemoveItem(module));
}
// FindModule
Module *
ModuleList::FindModule(const char *path)
{
if (path) {
for (int32 i = 0; Module *module = ModuleAt(i); i++) {
if (!strcmp(path, module->Info()->name))
return module;
}
}
return NULL;
}
// ModuleManager
class ModuleManager {
public:
ModuleManager();
~ModuleManager();
static ModuleManager *Default() { return &fDefaultManager; }
status_t GetModule(const char *path, module_info **infop);
status_t PutModule(const char *path);
status_t GetNextLoadedModuleName(uint32 *cookie, char *buffer,
size_t *bufferSize);
module_name_list *OpenModuleList(const char *prefix);
status_t ReadNextModuleName(module_name_list *list, char *buffer,
size_t *bufferSize);
status_t CloseModuleList(module_name_list *list);
private:
void _FindModules(BDirectory &dir, module_name_list *list);
private:
static ModuleManager fDefaultManager;
ModuleList fModules;
};
// constructor
ModuleManager::ModuleManager()
: fModules()
{
}
// destructor
ModuleManager::~ModuleManager()
{
for (int32 i = 0; Module *module = fModules.ModuleAt(i); i++)
delete module;
}
// GetModule
status_t
ModuleManager::GetModule(const char *path, module_info **infop)
{
status_t error = (path && infop ? B_OK : B_BAD_VALUE);
if (error == B_OK) {
BAutolock _lock(fModules);
Module *module = fModules.FindModule(path);
if (!module) {
module = new Module;
error = module->Init(path);
if (error == B_OK && !fModules.AddModule(module))
error = B_NO_MEMORY;
if (error == B_OK) {
module->Get();
*infop = module->Info();
} else
delete module;
}
}
return error;
}
// PutModule
status_t
ModuleManager::PutModule(const char *path)
{
status_t error = (path ? B_OK : B_BAD_VALUE);
if (error == B_OK) {
BAutolock _lock(fModules);
if (Module *module = fModules.FindModule(path)) {
if (module->Put()) {
fModules.RemoveModule(module);
delete module;
}
} else
error = B_BAD_VALUE;
}
return error;
}
// GetNextLoadedModuleName
status_t
ModuleManager::GetNextLoadedModuleName(uint32 *cookie, char *buffer,
size_t *bufferSize)
{
status_t error = (cookie && buffer && bufferSize ? B_OK : B_BAD_VALUE);
if (error == B_OK) {
BAutolock _lock(fModules);
if (Module *module = fModules.ModuleAt(*cookie)) {
module_info *info = module->Info();
size_t nameLen = strlen(info->name);
if (nameLen < *bufferSize) {
strcpy(buffer, info->name);
*bufferSize = nameLen;
(*cookie)++;
} else
error = B_BAD_VALUE;
} else
error = B_ENTRY_NOT_FOUND;
}
return error;
}
// OpenModuleList
module_name_list *
ModuleManager::OpenModuleList(const char *prefix)
{
module_name_list *list = NULL;
if (prefix) {
list = new module_name_list;
for (int32 i = 0; gModuleDirs[i]; i++) {
BPath path;
BDirectory dir;
if (path.SetTo(gModuleDirs[i], prefix) == B_OK
&& dir.SetTo(path.Path()) == B_OK) {
_FindModules(dir, list);
}
}
list->it = list->names.begin();
}
return list;
}
// ReadNextModuleName
status_t
ModuleManager::ReadNextModuleName(module_name_list *list, char *buffer,
size_t *bufferSize)
{
status_t error = (list && buffer && bufferSize ? B_OK : B_BAD_VALUE);
if (error == B_OK) {
if (list->it != list->names.end()) {
const string &name = *list->it;
size_t nameLen = name.length();
if (nameLen < *bufferSize) {
strcpy(buffer, name.c_str());
*bufferSize = nameLen;
list->it++;
} else
error = B_BAD_VALUE;
} else
error = B_ENTRY_NOT_FOUND;
}
return error;
}
// CloseModuleList
status_t
ModuleManager::CloseModuleList(module_name_list *list)
{
status_t error = (list ? B_OK : B_BAD_VALUE);
if (error == B_OK)
delete list;
return error;
}
// _FindModules
void
ModuleManager::_FindModules(BDirectory &dir, module_name_list *list)
{
BEntry entry;
while (dir.GetNextEntry(&entry) == B_OK) {
if (entry.IsFile()) {
Module module;
BPath path;
if (entry.GetPath(&path) == B_OK
&& module.Init(path.Path(), true) == B_OK) {
list->names.insert(module.Info()->name);
}
} else if (entry.IsDirectory()) {
BDirectory subdir;
if (subdir.SetTo(&entry) == B_OK)
_FindModules(subdir, list);
}
}
}
// singleton instance
ModuleManager ModuleManager::fDefaultManager;
// the functions to be emulated follow
// get_module
status_t
get_module(const char *path, module_info **vec)
{
TRACE(("get_module(`%s')\n", path));
return ModuleManager::Default()->GetModule(path, vec);
}
// put_module
status_t
put_module(const char *path)
{
TRACE(("put_module(`%s')\n", path));
return ModuleManager::Default()->PutModule(path);
}
// get_next_loaded_module_name
status_t
get_next_loaded_module_name(uint32 *cookie, char *buf, size_t *bufsize)
{
TRACE(("get_next_loaded_module_name(%lu)\n", *cookie));
return ModuleManager::Default()->GetNextLoadedModuleName(cookie, buf,
bufsize);
}
// open_module_list
void *
open_module_list(const char *prefix)
{
TRACE(("open_module_list(`%s')\n", prefix));
return (void*)ModuleManager::Default()->OpenModuleList(prefix);
}
// read_next_module_name
status_t
read_next_module_name(void *cookie, char *buf, size_t *bufsize)
{
TRACE(("read_next_module_name(%p, %p, %lu)\n", cookie, buf, *bufsize));
return ModuleManager::Default()->ReadNextModuleName(
(module_name_list*)cookie, buf, bufsize);
}
// close_module_list
status_t
close_module_list(void *cookie)
{
TRACE(("close_module_list(%p)\n", cookie));
return ModuleManager::Default()->CloseModuleList(
(module_name_list*)cookie);
}
// dprintf
void
dprintf(const char *format,...)
{
va_list args;
va_start(args, format);
vprintf(format, args);
va_end(args);
}