implement prover stdin reading

src/tasking/syscalls.c

@@ -152,19 +152,55 @@ int sys_fork(TrapFrame *tf)
     return child->pid;
 }
 
+#include "../../include/keyboard.h"
 int sys_read(TrapFrame *tf)
 {
-    if(tf->ebx < 3)
+    int fd = tf->ebx;
+    char *user_buf = (char *)tf->ecx;
+    size_t count = tf->edx;
+
+    if (fd == STDIN_FILENO) {
+        scheduler_lock();
+        while (!stdin_has_line) {//while enter has not been pressed
+            current->state = Waiting;
+            current->waiting_reason = STDIN;
+            schedule();
+        }
+        scheduler_unlock();
+
+        //find the pos of the first \n
+        int line_len = 0;
+        while (line_len < stdin_pos && stdin_buffer[line_len] != '\n') line_len++;
+        if (line_len < stdin_pos) line_len++;
+
+        //copy the input to the user buffer
+        int to_copy = (line_len < count) ? line_len : count;
+        memcpy(user_buf, stdin_buffer, to_copy);
+
+        memmove(stdin_buffer, stdin_buffer + to_copy, stdin_pos - to_copy);
+        stdin_pos -= to_copy;
+
+        stdin_has_line = false;
+        for (int i = 0; i < stdin_pos; i++) {
+            if (stdin_buffer[i] == '\n') {
+                stdin_has_line = true;
+                break;
+            }
+        }
+
+        return to_copy;
+    }
+    else if(fd < 3)
     {
-        //TODO: implement stdin handling here
+        return -EBADF;
     }
     else
     {
-        if(current->file_descriptors[tf->ebx] == NULL)
+        if(current->file_descriptors[fd] == NULL)
         {
             return -EBADF;
         }
-        return vfs_read_file_length(current->file_descriptors[tf->ebx], (uint8_t*)tf->ecx, tf->edx);
+        return vfs_read_file_length(current->file_descriptors[fd], (uint8_t*)user_buf, count);
         //return 0;//fat_fread(current->file_descriptors[tf->ebx], (void*)tf->ecx, tf->edx);
     }
 }
@@ -497,7 +533,7 @@ uint32_t sys_getcwd(TrapFrame *tf)
 
     //strcpy((char*)tf->ebx, current->cwd->fat->path);
     
-    return tf->ebx;
+    return strlen(final_path);//tf->ebx;
 }
 
 int sys_getpid(TrapFrame *tf)
@@ -551,6 +587,7 @@ uint32_t sys_nanosleep(TrapFrame *tf)
     scheduler_lock();
     current->wake_up_time = timer_ticks + ms;
     current->state = Waiting;
+    current->waiting_reason = TIMER;
     schedule();
     scheduler_unlock();
     
@@ -566,7 +603,7 @@ void handle_syscall(TrapFrame *tf)
     debug_log("EDX: %X\n", tf->edx);
     */
 
-    debug_log("calling 0x%X\n", tf->eax);
+    //debug_log("calling 0x%X\n", tf->eax);
 
     switch(tf->eax)
     {