文件描述符自动回收支持

mkrtos_user/lib/fd/fd.c

@@ -0,0 +1,114 @@
+
+#include "u_types.h"
+#include "u_hd_man.h"
+#include <u_mutex.h>
+#include <errno.h>
+#include <stdio.h>
+#include <u_sig.h>
+#include "fd.h"
+
+#define FILE_DESC_NR_OPEN 8
+static file_desc_t file_desc[FILE_DESC_NR_OPEN];
+static u_mutex_t fds_lock;
+
+static int fs_sig_call_back(pid_t pid, umword_t sig_val)
+{
+    switch (sig_val)
+    {
+    case KILL_SIG:
+        file_desc_recycle(pid);
+        break;
+    }
+    return 0;
+}
+
+int file_desc_init(void)
+{
+    int ret;
+    obj_handler_t sema_hd;
+
+    sema_hd = handler_alloc();
+    if (sema_hd == HANDLER_INVALID)
+    {
+        return -ENOMEM;
+    }
+    ret = u_mutex_init(&fds_lock, sema_hd);
+    if (ret < 0)
+    {
+        return ret;
+    }
+    pm_sig_func_set(fs_sig_call_back);
+    return ret;
+}
+int file_desc_alloc(pid_t pid, void *priv, void (*close_fn)(int fd))
+{
+    u_mutex_lock(&fds_lock, 0, NULL);
+    for (int i = 0; i < FILE_DESC_NR_OPEN; i++)
+    {
+        if (file_desc[i].close == NULL)
+        {
+            file_desc[i].pid = pid;
+            file_desc[i].priv = priv;
+            file_desc[i].close = close_fn;
+            u_mutex_unlock(&fds_lock);
+            return i;
+        }
+    }
+    u_mutex_unlock(&fds_lock);
+    return -ENOMEM;
+}
+int file_desc_set_priv(int fd, void *priv)
+{
+    if (fd < 0 || fd >= FILE_DESC_NR_OPEN)
+    {
+        return -EBADF;
+    }
+    file_desc[fd].priv = priv;
+    return 0;
+}
+file_desc_t *file_desc_get(int fd)
+{
+    if (fd < 0 || fd >= FILE_DESC_NR_OPEN)
+    {
+        return NULL;
+    }
+    return &file_desc[fd];
+}
+void *file_desc_free_unlock(int fd)
+{
+    void *ret;
+
+    if (fd < 0 || fd >= FILE_DESC_NR_OPEN)
+    {
+        return NULL;
+    }
+    file_desc[fd].pid = 0;
+    ret = file_desc[fd].priv;
+    file_desc[fd].priv = NULL;
+    file_desc[fd].close = NULL;
+    return ret;
+}
+void *file_desc_free(int fd)
+{
+    void *ret;
+
+    u_mutex_lock(&fds_lock, 0, NULL);
+    ret = file_desc_free_unlock(fd);
+    u_mutex_unlock(&fds_lock);
+    return ret;
+}
+void file_desc_recycle(pid_t pid)
+{
+    int free_cn = 0;
+
+    u_mutex_lock(&fds_lock, 0, NULL);
+    for (int i = 0; i < FILE_DESC_NR_OPEN; i++)
+    {
+        if (file_desc[i].close != NULL && file_desc[i].pid == pid)
+        {
+            file_desc[i].close(i);
+            printf("free fd:%d.\n", i);
+        }
+    }
+    u_mutex_unlock(&fds_lock);
+}