diff options
Diffstat (limited to 'libusb/libusbi.h')
| -rw-r--r-- | libusb/libusbi.h | 153 |
1 files changed, 141 insertions, 12 deletions
diff --git a/libusb/libusbi.h b/libusb/libusbi.h index 491114b..b1fc88c 100644 --- a/libusb/libusbi.h +++ b/libusb/libusbi.h @@ -83,6 +83,34 @@ #define PTR_ALIGN(v) \ (((v) + (sizeof(void *) - 1)) & ~(sizeof(void *) - 1)) +/* Atomic operations + * + * Useful for reference counting or when accessing a value without a lock + * + * The following atomic operations are defined: + * usbi_atomic_load() - Atomically read a variable's value + * usbi_atomic_store() - Atomically write a new value value to a variable + * usbi_atomic_inc() - Atomically increment a variable's value and return the new value + * usbi_atomic_dec() - Atomically decrement a variable's value and return the new value + * + * All of these operations are ordered with each other, thus the effects of + * any one operation is guaranteed to be seen by any other operation. + */ +#ifdef _MSC_VER +typedef volatile LONG usbi_atomic_t; +#define usbi_atomic_load(a) (*(a)) +#define usbi_atomic_store(a, v) (*(a)) = (v) +#define usbi_atomic_inc(a) InterlockedIncrement((a)) +#define usbi_atomic_dec(a) InterlockedDecrement((a)) +#else +#include <stdatomic.h> +typedef atomic_long usbi_atomic_t; +#define usbi_atomic_load(a) atomic_load((a)) +#define usbi_atomic_store(a, v) atomic_store((a), (v)) +#define usbi_atomic_inc(a) (atomic_fetch_add((a), 1) + 1) +#define usbi_atomic_dec(a) (atomic_fetch_add((a), -1) - 1) +#endif + /* Internal abstractions for event handling and thread synchronization */ #if defined(PLATFORM_POSIX) #include "os/events_posix.h" @@ -289,22 +317,23 @@ void usbi_log(struct libusb_context *ctx, enum libusb_log_level level, #define usbi_err(ctx, ...) _usbi_log(ctx, LIBUSB_LOG_LEVEL_ERROR, __VA_ARGS__) #define usbi_warn(ctx, ...) _usbi_log(ctx, LIBUSB_LOG_LEVEL_WARNING, __VA_ARGS__) #define usbi_info(ctx, ...) _usbi_log(ctx, LIBUSB_LOG_LEVEL_INFO, __VA_ARGS__) -#define usbi_dbg(...) _usbi_log(NULL, LIBUSB_LOG_LEVEL_DEBUG, __VA_ARGS__) +#define usbi_dbg(ctx ,...) _usbi_log(ctx, LIBUSB_LOG_LEVEL_DEBUG, __VA_ARGS__) #else /* ENABLE_LOGGING */ #define usbi_err(ctx, ...) UNUSED(ctx) #define usbi_warn(ctx, ...) UNUSED(ctx) #define usbi_info(ctx, ...) UNUSED(ctx) -#define usbi_dbg(...) do {} while (0) +#define usbi_dbg(ctx, ...) do {} while (0) #endif /* ENABLE_LOGGING */ #define DEVICE_CTX(dev) ((dev)->ctx) -#define HANDLE_CTX(handle) (DEVICE_CTX((handle)->dev)) -#define TRANSFER_CTX(transfer) (HANDLE_CTX((transfer)->dev_handle)) +#define HANDLE_CTX(handle) ((handle) ? DEVICE_CTX((handle)->dev) : NULL) #define ITRANSFER_CTX(itransfer) \ - (TRANSFER_CTX(USBI_TRANSFER_TO_LIBUSB_TRANSFER(itransfer))) + ((itransfer)->dev ? DEVICE_CTX((itransfer)->dev) : NULL) +#define TRANSFER_CTX(transfer) \ + (ITRANSFER_CTX(LIBUSB_TRANSFER_TO_USBI_TRANSFER(transfer))) #define IS_EPIN(ep) (0 != ((ep) & LIBUSB_ENDPOINT_IN)) #define IS_EPOUT(ep) (!IS_EPIN(ep)) @@ -340,6 +369,9 @@ struct libusb_context { libusb_hotplug_callback_handle next_hotplug_cb_handle; usbi_mutex_t hotplug_cbs_lock; + /* A flag to indicate that the context is ready for hotplug notifications */ + usbi_atomic_t hotplug_ready; + /* this is a list of in-flight transfer handles, sorted by timeout * expiration. URBs to timeout the soonest are placed at the beginning of * the list, URBs that will time out later are placed after, and urbs with @@ -404,13 +436,26 @@ struct libusb_context { }; extern struct libusb_context *usbi_default_context; +extern struct libusb_context *usbi_fallback_context; extern struct list_head active_contexts_list; extern usbi_mutex_static_t active_contexts_lock; static inline struct libusb_context *usbi_get_context(struct libusb_context *ctx) { - return ctx ? ctx : usbi_default_context; + static int warned = 0; + + if (!ctx) { + ctx = usbi_default_context; + } + if (!ctx) { + ctx = usbi_fallback_context; + if (ctx && warned == 0) { + usbi_err(ctx, "API misuse! Using non-default context as implicit default."); + warned = 1; + } + } + return ctx; } enum usbi_event_flags { @@ -450,10 +495,7 @@ static inline void usbi_end_event_handling(struct libusb_context *ctx) } struct libusb_device { - /* lock protects refcnt, everything else is finalized at initialization - * time */ - usbi_mutex_t lock; - int refcnt; + usbi_atomic_t refcnt; struct libusb_context *ctx; struct libusb_device *parent_dev; @@ -467,7 +509,7 @@ struct libusb_device { unsigned long session_data; struct libusb_device_descriptor device_descriptor; - int attached; + usbi_atomic_t attached; }; struct libusb_device_handle { @@ -534,6 +576,10 @@ struct usbi_transfer { uint32_t state_flags; /* Protected by usbi_transfer->lock */ uint32_t timeout_flags; /* Protected by the flying_stransfers_lock */ + /* The device reference is held until destruction for logging + * even after dev_handle is set to NULL. */ + struct libusb_device *dev; + /* this lock is held during libusb_submit_transfer() and * libusb_cancel_transfer() (allowing the OS backend to prevent duplicate * cancellation, submission-during-cancellation, etc). the OS backend @@ -664,8 +710,75 @@ union usbi_bos_desc_buf { uint16_t align; /* Force 2-byte alignment */ }; +enum usbi_hotplug_flags { + /* This callback is interested in device arrivals */ + USBI_HOTPLUG_DEVICE_ARRIVED = LIBUSB_HOTPLUG_EVENT_DEVICE_ARRIVED, + + /* This callback is interested in device removals */ + USBI_HOTPLUG_DEVICE_LEFT = LIBUSB_HOTPLUG_EVENT_DEVICE_LEFT, + + /* IMPORTANT: The values for the below entries must start *after* + * the highest value of the above entries!!! + */ + + /* The vendor_id field is valid for matching */ + USBI_HOTPLUG_VENDOR_ID_VALID = (1U << 3), + + /* The product_id field is valid for matching */ + USBI_HOTPLUG_PRODUCT_ID_VALID = (1U << 4), + + /* The dev_class field is valid for matching */ + USBI_HOTPLUG_DEV_CLASS_VALID = (1U << 5), + + /* This callback has been unregistered and needs to be freed */ + USBI_HOTPLUG_NEEDS_FREE = (1U << 6), +}; + +struct usbi_hotplug_callback { + /* Flags that control how this callback behaves */ + uint8_t flags; + + /* Vendor ID to match (if flags says this is valid) */ + uint16_t vendor_id; + + /* Product ID to match (if flags says this is valid) */ + uint16_t product_id; + + /* Device class to match (if flags says this is valid) */ + uint8_t dev_class; + + /* Callback function to invoke for matching event/device */ + libusb_hotplug_callback_fn cb; + + /* Handle for this callback (used to match on deregister) */ + libusb_hotplug_callback_handle handle; + + /* User data that will be passed to the callback function */ + void *user_data; + + /* List this callback is registered in (ctx->hotplug_cbs) */ + struct list_head list; +}; + +struct usbi_hotplug_message { + /* The hotplug event that occurred */ + libusb_hotplug_event event; + + /* The device for which this hotplug event occurred */ + struct libusb_device *device; + + /* List this message is contained in (ctx->hotplug_msgs) */ + struct list_head list; +}; + /* shared data and functions */ +void usbi_hotplug_init(struct libusb_context *ctx); +void usbi_hotplug_exit(struct libusb_context *ctx); +void usbi_hotplug_notification(struct libusb_context *ctx, struct libusb_device *dev, + libusb_hotplug_event event); +void usbi_hotplug_process(struct libusb_context *ctx, struct list_head *hotplug_msgs); + int usbi_io_init(struct libusb_context *ctx); void usbi_io_exit(struct libusb_context *ctx); @@ -696,6 +809,13 @@ int usbi_add_event_source(struct libusb_context *ctx, usbi_os_handle_t os_handle short poll_events); void usbi_remove_event_source(struct libusb_context *ctx, usbi_os_handle_t os_handle); +struct usbi_option { + int is_set; + union { + int ival; + } arg; +}; + /* OS event abstraction */ int usbi_create_event(usbi_event_t *event); @@ -793,7 +913,8 @@ struct usbi_os_backend { * data structures for later, etc. * * This function is called when a libusb user initializes the library - * prior to use. + * prior to use. Mutual exclusion with other init and exit calls is + * guaranteed when this function is called. * * Return 0 on success, or a LIBUSB_ERROR code on failure. */ @@ -803,6 +924,8 @@ struct usbi_os_backend { * that was set up by init. * * This function is called when the user deinitializes the library. + * Mutual exclusion with other init and exit calls is guaranteed when + * this function is called. */ void (*exit)(struct libusb_context *ctx); @@ -1365,6 +1488,12 @@ extern const struct usbi_os_backend usbi_backend; #define for_each_removed_event_source_safe(ctx, e, n) \ for_each_safe_helper(e, n, &(ctx)->removed_event_sources, struct usbi_event_source) +#define for_each_hotplug_cb(ctx, c) \ + for_each_helper(c, &(ctx)->hotplug_cbs, struct usbi_hotplug_callback) + +#define for_each_hotplug_cb_safe(ctx, c, n) \ + for_each_safe_helper(c, n, &(ctx)->hotplug_cbs, struct usbi_hotplug_callback) + #ifdef __cplusplus } #endif |