did this while lecture (builtins, parsing, exec and env by stdlib)

11 files changed, 230 insertions, 60 deletions

diff --git a/smash/Makefile b/smash/Makefile
index 4deb244..8a0dcee 100644
--- a/smash/Makefile
+++ b/smash/Makefile
@@ -1,3 +1,5 @@
+default_target: all
+
 unit_test_parser:
 	gcc parser.c ../lib/cstr/cstr.c ../lib/malloc/malloc.c ../lib/sys/start.S -static -nostdlib -fno-stack-protector -Wno-implicit-function-declaration -o test -DPARSER_UNIT_TEST -g
 	./test
@@ -5,3 +7,10 @@ unit_test_parser:
 unit_test_variables:
 	gcc variables.c ../lib/avl_tree/avl_tree.c ../lib/cstr/cstr.c ../lib/malloc/malloc.c ../lib/sys/start.S -static -nostdlib -fno-stack-protector -o test -DVARIABLES_UNIT_TEST -g
 	./test
+
+unit_test_builtin:
+	gcc builtin.c ../lib/cstr/cstr.c ../lib/sys/start.S -static -nostdlib -fno-stack-protector -Wno-implicit-function-declaration -o test -DBUILTIN_UNIT_TEST -g
+	./test
+
+all:
+	gcc main.c exec.c parser.c builtin.c ../lib/avl_tree/avl_tree.c ../lib/cstr/cstr.c ../lib/malloc/malloc.c ../lib/sys/start.S -static -nostdlib -fno-stack-protector -Wno-implicit-function-declaration -o smash -DVARIABLES_UNIT_TEST -g
diff --git a/smash/builtin.c b/smash/builtin.c
new file mode 100644
index 0000000..ad9c839
--- /dev/null
+++ b/smash/builtin.c
@@ -0,0 +1,86 @@
+#include "builtin.h"
+
+#include "../lib/sys/exit.h"
+#include "../lib/cstr/cstr.h"
+#include "../lib/sys/io.h"
+
+u64 __find_builtin_function_by_name(const char *name);
+
+int __builtin_fn_exit(int argc, const char **argv);
+int __builtin_fn_cd(int argc, const char **argv);
+int __builtin_fn_help(int argc, const char **argv);
+
+char *builtin_names[] = {
+	"exit",
+	"cd",
+	"help",
+	0
+};
+
+int (*builtin_functions[])(int argc, const char **argv) = {
+	__builtin_fn_exit,
+	__builtin_fn_cd,
+	__builtin_fn_help
+};
+
+int __builtin_fn_exit(int argc, const char **argv)
+{
+	exit(0);
+}
+
+int __builtin_fn_cd(int argc, const char **argv)
+{
+	/* TODO: Implement */
+}
+
+int __builtin_fn_help(int argc, const char **argv)
+{
+	write(STDOUT_FD, "This is the help page...\n", 25);
+	write(STDOUT_FD, "TODO: help page\n", 16);
+	return 0;
+}
+
+u64 __find_builtin_function_by_name(const char *name)
+{
+	char **p = builtin_names;
+
+	while (*p) {
+		if (cstr_compare(*p, name) == 0)
+			return p - builtin_names;
+		++p;
+	}
+
+	return -1;
+
+}
+
+u8 has_builtin_with_name(const char *name)
+{
+	return __find_builtin_function_by_name(name) != -1;
+}
+
+int run_builtin(const char *name, const char **argv)
+{
+	int argc = 0;
+	u64 builtin_index = __find_builtin_function_by_name(name);
+	const char **p = argv;
+	while (*p) {
+		++argc;
+		++p;
+	}
+
+	return builtin_functions[builtin_index](argc, argv);
+}
+
+#ifdef BUILTIN_UNIT_TEST
+
+int main() {
+	const char *argv[] = { "lelp", 0 };
+
+	if (has_builtin_with_name(argv[0]))
+		return run_builtin(argv[0], argv);
+
+	return 0;
+}
+
+#endif
diff --git a/smash/builtin.h b/smash/builtin.h
new file mode 100644
index 0000000..702268f
--- /dev/null
+++ b/smash/builtin.h
@@ -0,0 +1,9 @@
+#ifndef BUILTIN_H
+#define BUILTIN_H
+
+#include "../lib/sys/sizes.h"
+
+u8 has_builtin_with_name(const char *name);
+int run_builtin(const char *name, const char **argv);
+
+#endif
diff --git a/smash/exec.c b/smash/exec.c
new file mode 100644
index 0000000..3b62f41
--- /dev/null
+++ b/smash/exec.c
@@ -0,0 +1,84 @@
+#include "exec.h"
+
+#include "../lib/sys/execve.h"
+#include "../lib/sys/fork.h"
+#include "../lib/sys/wait4.h"
+#include "../lib/sys/pipe.h"
+#include "../lib/sys/dup2.h"
+#include "../lib/sys/close.h"
+#include "../lib/sys/io.h"
+#include "../lib/sys/exit.h"
+#include "../lib/cstr/cstr.h"
+
+#include "parser.h"
+#include "builtin.h"
+
+void print_call(char **argv)
+{
+	while (*argv) {
+		write(STDOUT_FD, *argv, cstr_length(*argv));
+		write(STDOUT_FD, "\n", 1);
+		++argv;
+	}
+}
+
+void exec(char *line)
+{
+	expression_list_t *exps = new_expression_from_line(line);
+	expression_list_t *exp = exps;
+	char **envp = { 0 };
+
+	int pid;
+	int pipefd[2][2];
+	pipefd[0][PIPE_IN] = STDOUT_FD;
+	pipefd[0][PIPE_OUT] = STDIN_FD;
+
+	while (exp) {
+		char **argv = new_argv(exp->call);
+
+		pipe(pipefd[1]);
+
+		if (has_builtin_with_name(argv[0])) {
+			run_builtin(argv[0], (const char**)argv);
+			break;
+		}
+
+		pid = fork();
+
+		if (pid == 0) {
+			if (pipefd[0][PIPE_OUT] != STDIN_FD) {
+				dup2(pipefd[0][PIPE_OUT], STDIN_FD);
+				close(pipefd[0][PIPE_OUT]);
+				close(pipefd[0][PIPE_IN]);
+			}
+			if (exp->next)
+				dup2(pipefd[1][PIPE_IN], STDOUT_FD);
+
+			close(pipefd[1][PIPE_OUT]);
+			close(pipefd[1][PIPE_IN]);
+
+			execve(argv[0], argv, envp);
+			write(STDOUT_FD, "command not found: ", 19);
+			write(STDOUT_FD, argv[0], cstr_length(argv[0]));
+			write(STDOUT_FD, "\n", 1);
+			exit(-1);
+		}
+
+		if (pipefd[0][PIPE_OUT] != STDIN_FD) {
+			close(pipefd[0][PIPE_IN]);
+			close(pipefd[0][PIPE_OUT]);
+		}
+		close(pipefd[1][PIPE_IN]);
+
+		pipefd[0][0] = pipefd[1][0];
+		pipefd[0][1] = pipefd[1][1];
+
+		free_argv(argv);
+
+		wait4(pid, 0, 0);
+		exp = exp->next;
+	}
+
+	free_expression(exps);
+}
+
diff --git a/smash/exec.h b/smash/exec.h
new file mode 100644
index 0000000..74780b0
--- /dev/null
+++ b/smash/exec.h
@@ -0,0 +1,6 @@
+#ifndef EXEC_H
+#define EXEC_H
+
+void exec(char *line);
+
+#endif
diff --git a/smash/main.c b/smash/main.c
new file mode 100644
index 0000000..0b3dc20
--- /dev/null
+++ b/smash/main.c
@@ -0,0 +1,26 @@
+#include "exec.h"
+
+#include "../lib/sys/io.h"
+#include "../lib/cstr/cstr.h"
+
+#define BUFSIZ 1024
+
+void clear_buf(char *buf)
+{
+	for (int i = 0; i < BUFSIZ; ++i)
+		buf[i] = 0;
+}
+
+int main(int argc, char *argv[], char *envp[])
+{
+	char buf[BUFSIZ] = {0};
+	char prompt[] = "$ ";
+
+	while (1) {
+		write(STDOUT_FD, prompt, cstr_length(prompt));
+		read(STDIN_FD, buf, 1024);
+		buf[cstr_length(buf) - 1] = 0;
+		exec(buf);
+		clear_buf(buf);
+	}
+}
diff --git a/smash/parser.c b/smash/parser.c
index 22b9ccf..55a6fd2 100644
--- a/smash/parser.c
+++ b/smash/parser.c
@@ -52,14 +52,16 @@ void free_expression(expression_list_t *expression)
 }
 
 
-char **__new_argv(char *exp)
+char **new_argv(char *exp)
 {
 	u64 n = cstr_split(exp, ' ');
-	char **argv = malloc(sizeof(char*) * n + 1);
+	char **argv = malloc(sizeof(char*) * (n + 1));
 	u64 i = 0;
 	char *current = exp;
 	char *next;
 
+	argv[n] = 0;
+
 	for (; n > 0; --n) {
 		next = (char*)next_split(current);
 		strip_cstr(current, ' ');
@@ -70,68 +72,11 @@ char **__new_argv(char *exp)
 		current = next;
 	}
 
-	argv[i] = 0;
-
 	return argv;
 }
 
 
-void __free_argv(char **argv)
+void free_argv(char **argv)
 {
 	free(argv);
 }
-
-#ifdef PARSER_UNIT_TEST
-
-#include "../lib/sys/execve.h"
-#include "../lib/sys/fork.h"
-#include "../lib/sys/wait4.h"
-#include "../lib/sys/pipe.h"
-#include "../lib/sys/dup2.h"
-#include "../lib/sys/close.h"
-#include "../lib/sys/io.h"
-#include "../lib/sys/exit.h"
-
-int main() {
-	char in[] = "/bin/ls -a | /bin/wc -l";
-	expression_list_t *exps = new_expression_from_line(in);
-	expression_list_t *exp = exps;
-	char **envp = { 0 };
-
-	int pid[2];
-	int pipefd[2];
-
-	char **argv1 = __new_argv(exp->call);
-	char **argv2 = __new_argv(exp->next->call);
-
-	pipe(pipefd);
-	pid[0] = fork();
-
-	if (pid[0] == 0) {
-		close(pipefd[0]);
-		dup2(pipefd[1], STDOUT_FD);
-		close(pipefd[1]);
-
-		execve(argv1[0], argv1, envp);
-	} else {
-		pid[1] = fork();
-
-
-		close(pipefd[1]);
-
-		if (pid[1] == 0) {
-			dup2(pipefd[0], STDIN_FD);
-			close(pipefd[0]);
-
-			execve(argv2[0], argv2, envp);
-		} else {
-			close(pipefd[0]);
-			wait4(pid[0], 0, 0);
-			wait4(pid[1], 0, 0);
-		}
-	}
-
-	return 0;
-}
-
-#endif
diff --git a/smash/parser.h b/smash/parser.h
index 23eee88..60b344e 100644
--- a/smash/parser.h
+++ b/smash/parser.h
@@ -10,5 +10,7 @@ typedef struct expression_list_t__ {
 
 expression_list_t *new_expression_from_line(char *line);
 void              free_expression(expression_list_t *expression);
+char              **new_argv(char *exp);
+void              free_argv(char **argv);
 
 #endif
diff --git a/smash/smash b/smash/smash
new file mode 100755
index 0000000..5d0b5e3
--- /dev/null
+++ b/smash/smash
diff --git a/smash/test b/smash/test
index a76addd..d282011 100755
--- a/smash/test
+++ b/smash/test
diff --git a/smash/test.c b/smash/test.c
new file mode 100644
index 0000000..cb3f748
--- /dev/null
+++ b/smash/test.c
@@ -0,0 +1,3 @@
+int main() {
+	return 0;
+}