/* $Id$ */ /** @file driver.h */ #ifndef DRIVER_H #define DRIVER_H #include "debug.h" #include "helpers.hpp" #include "string.h" #include <string> #include <map> bool GetDriverParamBool(const char * const *parm, const char *name); int GetDriverParamInt(const char * const *parm, const char *name, int def); class Driver { public: virtual const char *Start(const char * const *parm) = 0; virtual void Stop() = 0; virtual ~Driver() { } enum Type { DT_BEGIN = 0, DT_SOUND = 0, DT_MUSIC, DT_VIDEO, DT_END, }; }; DECLARE_POSTFIX_INCREMENT(Driver::Type); class DriverFactoryBase { private: Driver::Type type; char *name; int priority; typedef std::map<std::string, DriverFactoryBase *> Drivers; static Drivers &GetDrivers() { static Drivers &s_drivers = *new Drivers(); return s_drivers; } static Driver **GetActiveDriver(Driver::Type type) { static Driver *s_driver[3] = { NULL, NULL, NULL }; return &s_driver[type]; } static const char *GetDriverTypeName(Driver::Type type) { static const char *driver_type_name[] = { "sound", "music", "video" }; return driver_type_name[type]; } protected: /** * Register a driver internally, based on its name. * @param name the name of the driver. * @note an assert() will be trigger if 2 driver with the same name try to register. */ void RegisterDriver(const char *name, Driver::Type type, int priority) { /* Don't register nameless Drivers */ if (name == NULL) return; this->name = strdup(name); this->type = type; this->priority = priority; /* Prefix the name with driver type to make it unique */ char buf[32]; strecpy(buf, GetDriverTypeName(type), lastof(buf)); strecpy(buf + 5, name, lastof(buf)); #if !defined(NDEBUG) /* NDEBUG disables asserts and gives a warning: unused variable 'P' */ std::pair<Drivers::iterator, bool> P = #endif /* !NDEBUG */ GetDrivers().insert(Drivers::value_type(buf, this)); assert(P.second); } public: DriverFactoryBase() : name(NULL) {} virtual ~DriverFactoryBase() { if (this->name != NULL) GetDrivers().erase(this->name); free(this->name); } /** * Find the requested driver and return its class. * @param name the driver to select. * @post Sets the driver so GetCurrentDriver() returns it too. */ static Driver *SelectDriver(const char *name, Driver::Type type) { if (GetDrivers().size() == 0) return NULL; if (*name == '\0') { /* Probe for this driver */ for (int priority = 10; priority >= 0; priority--) { Drivers::iterator it = GetDrivers().begin(); for (; it != GetDrivers().end(); ++it) { DriverFactoryBase *d = (*it).second; /* Check driver type */ if (d->type != type) continue; if (d->priority != priority) continue; Driver *newd = d->CreateInstance(); const char *err = newd->Start(NULL); if (err == NULL) { DEBUG(driver, 1, "Successfully probed %s driver '%s'", GetDriverTypeName(type), d->name); delete *GetActiveDriver(type); *GetActiveDriver(type) = newd; return newd; } DEBUG(driver, 1, "Probing %s driver '%s' failed with error: %s", GetDriverTypeName(type), d->name, err); delete newd; } } error("Couldn't find any suitable %s driver", GetDriverTypeName(type)); } else { char *parm; char buffer[256]; const char *parms[32]; /* Extract the driver name and put parameter list in parm */ strecpy(buffer, name, lastof(buffer)); parm = strchr(buffer, ':'); parms[0] = NULL; if (parm != NULL) { uint np = 0; /* Tokenize the parm. */ do { *parm++ = '\0'; if (np < lengthof(parms) - 1) parms[np++] = parm; while (*parm != '\0' && *parm != ',') parm++; } while (*parm == ','); parms[np] = NULL; } /* Find this driver */ Drivers::iterator it = GetDrivers().begin(); for (; it != GetDrivers().end(); ++it) { DriverFactoryBase *d = (*it).second; /* Check driver type */ if (d->type != type) continue; /* Check driver name */ if (strcasecmp(buffer, d->name) != 0) continue; /* Found our driver, let's try it */ Driver *newd = d->CreateInstance(); const char *err = newd->Start(parms); if (err != NULL) { delete newd; error("Unable to load driver '%s'. The error was: %s", d->name, err); } DEBUG(driver, 1, "Successfully loaded %s driver '%s'", GetDriverTypeName(type), d->name); delete *GetActiveDriver(type); *GetActiveDriver(type) = newd; return newd; } error("No such %s driver: %s\n", GetDriverTypeName(type), buffer); } } /** * Build a human readable list of available drivers, grouped by type. */ static char *GetDriversInfo(char *p, const char *last) { for (Driver::Type type = Driver::DT_BEGIN; type != Driver::DT_END; type++) { p += snprintf(p, last - p, "List of %s drivers:\n", GetDriverTypeName(type)); for (int priority = 10; priority >= 0; priority--) { Drivers::iterator it = GetDrivers().begin(); for (; it != GetDrivers().end(); it++) { DriverFactoryBase *d = (*it).second; if (d->type != type) continue; if (d->priority != priority) continue; p += snprintf(p, last - p, "%18s: %s\n", d->name, d->GetDescription()); } } p += snprintf(p, last - p, "\n"); } return p; } /** * Get a nice description of the driver-class. */ virtual const char *GetDescription() = 0; /** * Create an instance of this driver-class. */ virtual Driver *CreateInstance() = 0; }; #endif /* DRIVER_H */