Added driver interface, loading, hashmap

README.md

@@ -4,3 +4,17 @@ Manage the settings of your keyboard, mouse, ... with a simple GUI.
 This is for the internal settings of your devices, not for the OS settings.
 For example, you can change the mouse DPI, polling rate, rgb, ...
 
+## Driver interface
+
+Drivers **must** expose the following symbols:
+```c
+void driver_init(); // Initialization
+uint32_t driver_getkey(); // Calls to this function must return USB keys that this driver registers, until 0
+char* driver_get_name(); // Returns peripheral name
+char* driver_get_image(); // Returns peripheral image
+device_type_t driver_get_type(); // Returns device type
+
+// Mouse drivers
+
+```
+

src/device/usb/usb.c

@@ -1,20 +1,84 @@
 #include <libusb.h>
 #include <stdio.h>
 #include <stdlib.h>
+#include <dirent.h>
+#include <dlfcn.h>
+#include <string.h>
+#include <linux/limits.h>
+#include <unistd.h>
+#include <libgen.h>
 
 #include "device/device.h"
+#include "utils/hashmap.h"
+
+hashmap_t* usb_drivers;
+
+void usb_drivers_init()
+{
+    // Initialize hashmap
+    usb_drivers = hashmap_alloc();
+
+    // Obtain current executable path
+    char exe_path[PATH_MAX];
+    readlink("/proc/self/exe", exe_path, PATH_MAX);
+    
+    char* path = dirname(exe_path);
+    size_t path_len = strlen(path);
+
+    char driver_path[PATH_MAX];
+    memcpy(driver_path, path, path_len);
+    memcpy(driver_path + path_len, "/drivers/", 10);
+
+    // Open driver directory and load all symbols
+    DIR* directory = opendir(driver_path);
+    if(!directory)
+    {
+        fprintf(stderr, "Error: Could not open '%s' directory\n", driver_path);
+        return;
+    }
+
+    printf("Opened drivers directory: %s\n", driver_path);
+
+    struct dirent* entry;
+    while((entry = readdir(directory)))
+    {
+        if(entry->d_type & DT_DIR) continue;
+
+        size_t entry_name_len = strlen(entry->d_name);
+
+        char fullpath[PATH_MAX];
+        memcpy(fullpath, driver_path, path_len + 9);
+        memcpy(fullpath + path_len + 9, entry->d_name, entry_name_len);
+        *(fullpath + path_len + 9 + entry_name_len) = 0;
+        
+        void* driver = dlopen(fullpath, RTLD_LAZY | RTLD_LOCAL);
+        void (*init_fn)(void) = dlsym(driver, "driver_init");
+        init_fn();
+
+        uint32_t (*getkey_fn)(void) = dlsym(driver, "driver_getkey");
+        uint32_t key;
+        while((key = getkey_fn()))
+            hashmap_put(usb_drivers, key, driver);
+    }
+
+    closedir(directory);
+}
 
 void usb_init()
 {
-    // List all usb devices obtaining 'vendor:product'
-    // Call corresponding driver if it exists, so 
-    // that we get a peripheral handle
+    // Init drivers
+    usb_drivers_init();
+
+    // Init libusb
     if(libusb_init(NULL))
     {
         fprintf(stderr, "Error: Could not initialize libusb\n");
         return;
     }
 
+    // List all usb devices obtaining 'vendor:product'
+    // Call corresponding driver if it exists, so 
+    // that we get a peripheral handle
     libusb_device** list;
     ssize_t device_count = libusb_get_device_list(NULL, &list);
     if(device_count <= 0) return;
@@ -28,5 +92,13 @@ void usb_init()
         printf("Found usb device %04x:%04x\n", desc.idVendor, desc.idProduct);
         array_t* array = device_get_array();
         array_add(array, 0);
+
+        libusb_device_handle* handle;
+        libusb_open(current, &handle);
+        char buf[4096] = {0};
+        libusb_get_string_descriptor_ascii(handle, 1, buf, 4096);
+        printf("Device desc (1): %s\n", buf);
+        libusb_get_string_descriptor_ascii(handle, 2, buf, 4096);
+        printf("Device desc (2): %s\n", buf);
     }
 }

src/utils/hashmap.c

@@ -0,0 +1,76 @@
+#include "hashmap.h"
+#include <stdlib.h>
+
+#define HASHMAP_ARRAY_SIZE 512
+
+struct HASHMAP_ENTRY
+{
+    uint32_t key;
+    void* elem;
+    struct HASHMAP_ENTRY* next;    
+};
+
+struct HASHMAP
+{
+    struct HASHMAP_ENTRY** array;
+};
+
+size_t _hashmap_hash(uint32_t key)
+{
+    return key % HASHMAP_ARRAY_SIZE;
+}
+
+hashmap_t* hashmap_alloc()
+{
+    hashmap_t* tr = malloc(sizeof(hashmap_t));
+    tr->array = calloc(sizeof(struct HASHMAP_ENTRY*), HASHMAP_ARRAY_SIZE);
+    return tr;
+}
+
+void hashmap_free(hashmap_t* hashmap)
+{
+    for(size_t i = 0; i < HASHMAP_ARRAY_SIZE; i++)
+    {
+        struct HASHMAP_ENTRY* current = hashmap->array[i];
+
+        while(current)
+        {
+            struct HASHMAP_ENTRY* old = current;
+            current = current->next;
+            free(old);
+        }
+    }
+
+    free(hashmap->array);
+    free(hashmap);
+}
+
+void hashmap_put(hashmap_t* hashmap, uint32_t key, void* elem)
+{
+    size_t index = _hashmap_hash(key);
+    struct HASHMAP_ENTRY** current = &hashmap->array[index];
+
+    while(*current)
+    {
+        current = &(*current)->next;
+    }
+
+    (*current) = malloc(sizeof(struct HASHMAP_ENTRY));
+    (*current)->key = key;
+    (*current)->elem = elem;
+    (*current)->next = 0;
+}
+
+void* hashmap_get(hashmap_t* hashmap, uint32_t key)
+{
+    size_t index = _hashmap_hash(key);
+    struct HASHMAP_ENTRY* current = hashmap->array[index];
+
+    while(current)
+    {
+        if(current->key == key) return current->elem;
+        current = current->next;
+    }
+
+    return 0;
+}

src/utils/hashmap.h

@@ -0,0 +1,15 @@
+#ifndef HASHMAP_H
+#define HASHMAP_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+typedef struct HASHMAP hashmap_t;
+
+hashmap_t* hashmap_alloc();
+void hashmap_free(hashmap_t* hashmap);
+
+void hashmap_put(hashmap_t* hashmap, uint32_t key, void* elem);
+void* hashmap_get(hashmap_t* hashmap, uint32_t key);
+
+#endif