From 3653e558f949ad876a19871ad64f80b7fecd8cc0 Mon Sep 17 00:00:00 2001
From: starnakin <camille@chauvet.pro>
Date: Sun, 2 Jul 2023 12:10:28 +0200
Subject: [PATCH] add: redirections

---
 src/exec/exec.c               |   4 +-
 src/parsing/parsing.c         |   2 +
 src/redirection/redirection.c | 113 +++++++++++++++++++++++++++++++++-
 src/redirection/redirection.h |  11 ++++
 4 files changed, 128 insertions(+), 2 deletions(-)
 create mode 100644 src/redirection/redirection.h

diff --git a/src/exec/exec.c b/src/exec/exec.c
index a2209f9..e25b007 100644
--- a/src/exec/exec.c
+++ b/src/exec/exec.c
@@ -93,7 +93,9 @@ int cmds_list_exec(lst** cmds, lst** env)
 			content->fd_out = fds[1];
 			((cmd*)current->next->content)->fd_in = fds[0];
 		}
-		if (content->executable == NULL)
+		if (content->args[0] == NULL)
+			;
+		else if (content->executable == NULL)
 			dprintf(2, "zzsh: command not found: %s\n", content->args[0]);
 		else if (builtin_execute(content, env) == 1)
 			execute(content, env);
diff --git a/src/parsing/parsing.c b/src/parsing/parsing.c
index 4cab058..56cdfc2 100644
--- a/src/parsing/parsing.c
+++ b/src/parsing/parsing.c
@@ -1,6 +1,8 @@
 #include "parsing.h"
 char* parsing_executable(const char* executable, lst** env)
 {
+	if (executable == NULL)
+		return NULL;
 	if (strchr("./", executable[0]))
 		return strdup(executable);
 	return (get_executable_path(executable, env));
diff --git a/src/redirection/redirection.c b/src/redirection/redirection.c
index 44bc1f8..67e733f 100644
--- a/src/redirection/redirection.c
+++ b/src/redirection/redirection.c
@@ -1,3 +1,114 @@
-#include "../../lib/bozolib/bozolib.h"
+#include "./redirection.h"
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
 
+char* get_path(const char* start_path)
+{
+	size_t i, j;
+	char* out;
 
+	i = 0;
+	while (strchr(" \t", start_path[i]))
+		i++;
+	j = i;
+	while (start_path[j] != '\0' && strchr(" \t", start_path[j]) == NULL) 
+		j++;
+	if (str_contain_only(start_path + i, "\t "))
+		return NULL;
+	out = strndup(start_path + i, j);
+	if (out == NULL)
+	{
+		dprintf(2, "zzsh: malloc failed\n");
+		return NULL;
+	}
+	quote_remover(out);
+	return out;
+}
+
+static size_t get_path_size(const char* str)
+{
+	size_t i = 0;
+	while (strchr("\t ", str[i]) != NULL)
+		i++;
+	while (str[i] != '\0' && strchr("\t ", str[i]) == NULL)
+		i++;
+	return i;
+}
+
+int redirection_fill(const char* str, size_t nb_symbols, cmd* command, const char *path)
+{
+	int problem = 0;
+	if (str[0] == '>')
+	{
+		if (command->fd_out > 2)
+			close(command->fd_out);
+		if (nb_symbols == 1)
+			command->fd_out = open(path, O_TRUNC | O_CREAT | O_WRONLY, 0644);
+		else
+			command->fd_out = open(path, O_APPEND | O_CREAT | O_WRONLY, 0644);
+		problem = command->fd_out == -1;
+	}
+	else
+	{
+		if (command->fd_in > 2)
+			close(command->fd_in);
+		if (nb_symbols == 1)
+			command->fd_in = open(path, O_RDONLY);
+		else
+			command->fd_in = open(path, O_RDONLY);
+		problem = command->fd_in == -1;
+	}
+	if (problem)
+		dprintf(2, "zzsh: \"%s\": file error\n", path);
+	return problem;
+}
+
+static size_t get_concecutive(const char *str)
+{
+	size_t i;
+	for (i = 1; str[i] == str[0]; i++);
+	return (i);
+}
+
+int get_redirections(char *str, cmd* command)
+{
+	char *redirection;
+	char redirection_symbol[3] = "<>";
+	char *path;
+	size_t redirection_type;
+
+	for (size_t i = 0; redirection_symbol[i] != '\0'; i++)
+	{
+		redirection = str;
+		while (redirection != NULL)
+		{
+			redirection = strchr(redirection, redirection_symbol[i]);
+			while (redirection != NULL && is_in_quote(str, redirection - str))
+				redirection = strchr(redirection, '>');
+			if (redirection == NULL)
+				break;
+			redirection_type = get_concecutive(redirection);
+			if (redirection_type > 2)
+			{
+				dprintf(2, "zzsh: invalid redirection type\n");
+				return 1;
+			}
+			else
+			{
+				path = get_path(redirection + redirection_type);
+				if (path == NULL)
+					return 1;
+				if (redirection_fill(redirection, redirection_type, command, path))
+				{
+					free(path);
+					return (1);
+				}
+				str_shift(redirection, (get_path_size(redirection + redirection_type) + redirection_type) * -1);
+				free(path);
+			}
+			redirection = redirection + redirection_type;
+		}
+	}
+	return (0);
+}
diff --git a/src/redirection/redirection.h b/src/redirection/redirection.h
new file mode 100644
index 0000000..a559dd8
--- /dev/null
+++ b/src/redirection/redirection.h
@@ -0,0 +1,11 @@
+#pragma once
+
+#include <stddef.h>
+#include <stdio.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include "../../lib/bozolib/bozolib.h"
+#include "../cmd/cmd.h"
+#include "../utils/utils.h"
+
+int get_redirections(char *str, cmd* command);