apps/src/sh.c

@@ -16,8 +16,7 @@ typedef struct
     char* buffer;
     size_t size;
     size_t capacity;
-    int interactive;
-} command_t;
+} command;
 
 char** split_command_into_argv(const char* cmd)
 {
@@ -79,19 +78,30 @@ void shell_execvp(char* pathname, char* const argv[])
 
 void show_prompt()
 {
+    if (!username)
+    {
+        struct passwd* user = getpwuid(getuid());
+        if (!user)
+        {
+            if (errno) perror("getpwuid");
+            username = "??";
+        }
+        else { username = user->pw_name; }
+        atexit(endpwent);
+    }
     if (WEXITSTATUS(status)) { printf("%d [%s]> ", WEXITSTATUS(status), username); }
     else
         printf("[%s]> ", username);
 }
 
-int command_matches(command_t* cmd, const char* string)
+int command_matches(command* cmd, const char* string)
 {
     if (cmd->size <= strlen(string)) // cmd->size includes null terminator
         return 0;
     return strncmp(cmd->buffer, string, strlen(string)) == 0;
 }
 
-int command_matches_exactly(command_t* cmd, const char* string)
+int command_matches_exactly(command* cmd, const char* string)
 {
     if (cmd->size <= strlen(string)) // cmd->size includes null terminator
         return 0;
@@ -99,7 +109,7 @@ int command_matches_exactly(command_t* cmd, const char* string)
     return strncmp(cmd->buffer, string, strlen(string)) == 0;
 }
 
-int command_match_builtins(command_t* cmd)
+int command_match_builtins(command* cmd)
 {
     if (command_matches(cmd, "exit ")) { exit(atoi(cmd->buffer + 5)); }
     if (command_matches_exactly(cmd, "exit")) { exit(0); }
@@ -116,7 +126,7 @@ int command_match_builtins(command_t* cmd)
     return 0;
 }
 
-void command_expand(command_t* cmd, long new_capacity)
+void command_expand(command* cmd, long new_capacity)
 {
     char* buffer = realloc(cmd->buffer, new_capacity);
     if (!buffer)
@@ -128,46 +138,38 @@ void command_expand(command_t* cmd, long new_capacity)
     cmd->capacity = new_capacity;
 }
 
-void command_push(command_t* cmd, char c)
+void command_push(command* cmd, char c)
 {
     if (cmd->size == cmd->capacity) command_expand(cmd, cmd->capacity + 8);
     cmd->buffer[cmd->size] = c;
     cmd->size++;
 }
 
-void command_pop(command_t* cmd)
+void command_pop(command* cmd)
 {
     cmd->size--;
 }
 
-void command_init(command_t* cmd)
+void command_init(command* cmd)
 {
     cmd->buffer = malloc(5);
     cmd->capacity = 5;
     cmd->size = 0;
 }
 
-void command_clear(command_t* cmd)
+void command_clear(command* cmd)
 {
     free(cmd->buffer);
     return command_init(cmd);
 }
 
-void process_execute_command(const char* command)
-{
-    char** argv = split_command_into_argv(command);
-    shell_execvp(argv[0], argv);
-    perror(argv[0]);
-    exit(127);
-}
-
-void command_execute(command_t* cmd)
+void command_execute(command* cmd)
 {
     command_push(cmd, '\0');
     if (command_match_builtins(cmd))
     {
         command_clear(cmd);
-        if (cmd->interactive) show_prompt();
+        show_prompt();
         return;
     }
     pid_t child = fork();
@@ -175,54 +177,60 @@ void command_execute(command_t* cmd)
     {
         perror("fork");
         command_clear(cmd);
-        if (cmd->interactive) show_prompt();
+        show_prompt();
         return;
     }
-    if (child == 0) process_execute_command(cmd->buffer);
+    if (child == 0)
+    {
+        char** argv = split_command_into_argv(cmd->buffer);
+        shell_execvp(argv[0], argv);
+        perror(argv[0]);
+        exit(127);
+    }
     pid_t result = waitpid(child, &status, 0);
     if (result < 0)
     {
         perror("waitpid");
         command_clear(cmd);
-        if (cmd->interactive) show_prompt();
+        show_prompt();
         return;
     }
     int exit_status = WEXITSTATUS(status);
     if (exit_status == -2 || exit_status == -3) printf("(PID %ld) Segmentation fault\n", result);
     if (exit_status == -1) printf("(PID %ld) Aborted\n", result);
     command_clear(cmd);
-    if (cmd->interactive) show_prompt();
+    show_prompt();
 }
 
-void command_concat_char(command_t* cmd, char c)
+void command_concat_char(command* cmd, char c)
 {
     if (c == '\b')
     {
         if (cmd->size != 0)
         {
-            if (cmd->interactive) putchar(c);
+            putchar(c);
             command_pop(cmd);
         }
     }
     else if (c == '\n')
     {
-        if (cmd->interactive) putchar(c);
+        putchar(c);
         if (cmd->size == 0)
         {
             status = 0;
-            if (cmd->interactive) show_prompt();
+            show_prompt();
         }
         else
             command_execute(cmd);
     }
     else
     {
-        if (cmd->interactive) putchar(c);
+        putchar(c);
         command_push(cmd, c);
     }
 }
 
-void command_concat(command_t* cmd, const char* str)
+void command_concat(command* cmd, const char* str)
 {
     while (*str)
     {
@@ -231,15 +239,13 @@ void command_concat(command_t* cmd, const char* str)
     }
 }
 
-void shell_interactive()
+int main()
 {
     show_prompt();
 
-    command_t shell_command;
+    command shell_command;
     command_init(&shell_command);
 
-    shell_command.interactive = 1;
-
     while (1)
     {
         int c = getchar();
@@ -248,112 +254,11 @@ void shell_interactive()
             if (ferror(stdin))
             {
                 perror("getchar");
-                exit(EXIT_FAILURE);
+                return 1;
             }
-            if (feof(stdin)) exit(EXIT_SUCCESS);
+            if (feof(stdin)) return 0;
             assert(false); // we should never get here
         }
         command_concat_char(&shell_command, (char)c);
     }
-}
-
-void shell_read_from_file(const char* pathname)
-{
-    FILE* fp = fopen(pathname, "r");
-    if (!fp)
-    {
-        perror("sh");
-        exit(EXIT_FAILURE);
-    }
-
-    command_t file_command;
-    command_init(&file_command);
-
-    file_command.interactive = 0;
-
-    char buffer[BUFSIZ];
-    while (fgets(buffer, BUFSIZ, fp))
-    {
-        command_concat(&file_command, buffer);
-        if (feof(fp)) break;
-    }
-
-    if (file_command.size > 0) // last line of file, does not end with newline
-    {
-        command_execute(&file_command);
-    }
-
-    fclose(fp);
-}
-
-void shell_execute_command(const char* command)
-{
-    command_t cmd;
-    cmd.buffer = strdup(command);
-    cmd.size = strlen(command) + 1;
-    if (command_match_builtins(&cmd)) return;
-    command_clear(&cmd);
-    process_execute_command(command);
-}
-
-void fetch_username()
-{
-    struct passwd* user = getpwuid(getuid());
-    if (!user)
-    {
-        perror("getpwuid");
-        exit(EXIT_FAILURE);
-    }
-    username = user->pw_name;
-    endpwent();
-}
-
-int main(int argc, char** argv)
-{
-    fetch_username();
-
-    if (argc == 1) shell_interactive();
-    else if (argc == 2)
-    {
-        if (!strcmp(argv[1], "-v") || !strcmp(argv[1], "--version"))
-        {
-            puts("Luna sh version 0.1"); // FIXME: Store the version somewhere, or use the kernel's version.
-            return 0;
-        }
-
-        if (!strcmp(argv[1], "-h") || !strcmp(argv[1], "--help"))
-        {
-            printf("To use interactively: %s\n", argv[0]);
-            printf("To run a script: %s [script-name]\n", argv[0]);
-            printf("To get help: %s --help\n", argv[0]);
-            printf("To show the version: %s --version\n", argv[0]);
-            printf("To run a command: %s -c [command]\n", argv[0]);
-            return 0;
-        }
-
-        if (!strcmp(argv[1], "-c") || !strcmp(argv[1], "--command"))
-        {
-            fprintf(stderr, "Usage: %s %s [command]\n", argv[0], argv[1]);
-            fprintf(stderr, "Use the --help flag for more help.\n");
-            return 1;
-        }
-
-        shell_read_from_file(argv[1]);
-    }
-    else if (argc == 3)
-    {
-        if (!strcmp(argv[1], "-c") || !strcmp(argv[1], "--command")) shell_execute_command(argv[2]);
-        else
-        {
-            fprintf(stderr, "%s: too many arguments\n", argv[0]);
-            fprintf(stderr, "Use the --help flag for more help.\n");
-            return 1;
-        }
-    }
-    else
-    {
-        fprintf(stderr, "%s: too many arguments\n", argv[0]);
-        fprintf(stderr, "Use the --help flag for more help.\n");
-        return 1;
-    }
 }

kernel/src/thread/Task.cpp

@@ -74,7 +74,11 @@ bool Task::has_died()
 
 void Task::resume_read()
 {
+    VMM::switch_back_to_kernel_address_space();
+    VMM::apply_address_space();
+    VMM::switch_to_previous_user_address_space();
     regs.rax = files[blocking_read_info.fd].read(blocking_read_info.size, blocking_read_info.buf);
+    VMM::apply_address_space();
 }
 
 bool Task::is_read_still_blocking()
@@ -84,9 +88,6 @@ bool Task::is_read_still_blocking()
 
 void Task::resume()
 {
-    VMM::switch_back_to_kernel_address_space();
-    VMM::apply_address_space();
-    VMM::switch_to_previous_user_address_space();
     switch (block_reason)
     {
     case BlockReason::None: ASSERT(false);
@@ -95,7 +96,6 @@ void Task::resume()
 
     default: ASSERT(false);
     }
-    VMM::apply_address_space();
     block_reason = BlockReason::None;
     state = Running;
 }