Added archive extracting

6 files changed, 149 insertions, 77 deletions

diff --git a/README.md b/README.md
index 95120ca..4c93688 100644
--- a/README.md
+++ b/README.md
@@ -4,10 +4,12 @@ Shitty clone of the `tar` program made for educational purposes.
 
 ## TODO
 
-- [ ] `x` Extracting archive
+- [x] `x` Extracting archive
 - [ ] `d` Difference between file system and archive
 - [ ] `t` List archive
 - [ ] `v` Verbose mode
 - [ ] `A` Concatenate 2 archives together
 - [ ] `r` Add files to archive
 - [ ] `u` Update file in archive
+- [ ] Remove `..` from member name
+- [ ] Complete ustar format
diff --git a/inc/tar.h b/inc/tar.h
index dbeca6d..66e3c64 100644
--- a/inc/tar.h
+++ b/inc/tar.h
@@ -65,10 +65,9 @@ typedef enum
 	FLAG_LIST = 1 << 0,
 }			t_flags;
 
-// utils.c
-int			record_write(int fd, char *s, size_t size);
-int			record_write_blank(int fd, size_t count);
+// header.c
 int			header_write(int fd, char *file_name, struct stat *statbuf);
+int			header_parse(char record[RECORD_SIZE], struct stat *statbuf, t_header *header);
 
 // fs.c
 int 		file_content_write(int fd, int file_fd, struct stat *statbuf);
@@ -79,4 +78,10 @@ int 		directory_write(int fd, char dir_name[PATH_MAX]);
 int			archive_write(char *archive_file_name, char **files);
 int			archive_read(char *archive_file_name);
 
+// record.c
+int			record_write(int fd, char *s, size_t size);
+int			record_write_blank(int fd, size_t count);
+int			record_read(int fd, char record[RECORD_SIZE]);
+bool		record_is_blank(char record[RECORD_SIZE]);
+
 #endif // TAR_H
diff --git a/src/archive.c b/src/archive.c
index 11457d6..a3addd3 100644
--- a/src/archive.c
+++ b/src/archive.c
@@ -41,33 +41,71 @@ int	archive_write(char *archive_file_name, char **files)
 
 int			archive_read(char *archive_file_name)
 {
-	int	fd;
+	int	archive_fd;
 
-	if ((fd = open(archive_file_name, O_RDONLY)) == -1)
+	if (archive_file_name == NULL)
+		archive_fd = STDIN_FILENO;
+	else
 	{
-		perror("achive_write");
-		return -1;
+		if ((archive_fd = open(archive_file_name, O_RDONLY)) == -1)
+		{
+			perror("achive_write");
+			return -1;
+		}
 	}
 
-	int			ret;
-	char		buf[RECORD_SIZE];
+	char		record[RECORD_SIZE];
 	t_header	header;
-	int			current_fd;
+	int			fd;
+	struct stat	statbuf;
 
-	while ((ret = read(fd, buf, RECORD_SIZE)) == RECORD_SIZE)
-	{
-		/* header_parse(&header, buf); */
-		/* current_fd = open(header.file_name, O_WRONLY | O_CREAT | O_TRUNC, header. */
-		// read content
-		// TODO
-	}
-	if (ret == -1)
+	while (true)
 	{
-		perror(NULL);
-		return -1;
+		if (record_read(archive_fd, record) == -1)
+			return -1;
+		if (record_is_blank(record))
+		{
+			if (record_read(archive_fd, record) == -1)
+				return -1;
+			if (record_is_blank(record))
+				break;
+			else
+				return -1;
+		}
+		if (header_parse(record, &statbuf, &header) == -1)
+			return -1;
+
+		switch (header.file_type[0])
+		{
+			case '5':
+				if (mkdir(header.file_name, statbuf.st_mode) == -1)
+				{
+					close(archive_fd);
+					perror(NULL);
+					return -1;
+				}
+				break;
+			case '0':
+				fd = open(header.file_name, O_WRONLY | O_CREAT | O_TRUNC, statbuf.st_mode);
+				if (fd == -1)
+				{
+					perror(NULL);
+					return -1;
+				}
+				char *content = malloc(statbuf.st_size);
+				if (content == NULL ||
+					read(archive_fd, content, statbuf.st_size) == -1 ||
+					lseek(archive_fd, RECORD_SIZE - statbuf.st_size % RECORD_SIZE, SEEK_CUR) == -1 ||
+					write(fd, content, statbuf.st_size) == -1)
+				{
+					perror(NULL);
+					return -1;
+				}
+				break;
+			default:
+				return -1;
+		}
 	}
-	if (ret < RECORD_SIZE)
-		return -1;
-	close(fd);
+	close(archive_fd);
 	return 0;
 }
diff --git a/src/fs.c b/src/fs.c
index 78ef25a..c285259 100644
--- a/src/fs.c
+++ b/src/fs.c
@@ -83,3 +83,5 @@ int directory_write(int fd, char dir_name[PATH_MAX])
 	closedir(dir);
 	return 0;
 }
+
+/* int	file_content_read(int archive_fd,  */
diff --git a/src/utils.c b/src/header.c
index ce56307..d881275 100644
--- a/src/utils.c
+++ b/src/header.c
@@ -1,44 +1,5 @@
 #include "tar.h"
 
-int	record_write(int fd, char *s, size_t size)
-{
-	char buf[RECORD_SIZE];
-
-	while (size > RECORD_SIZE)
-	{
-		memcpy(buf, s, RECORD_SIZE);
-		s += RECORD_SIZE;
-		size -= RECORD_SIZE;
-		if (write(fd, buf, RECORD_SIZE) == -1)
-		{
-			perror(NULL);
-			return -1;
-		}
-	}
-	bzero(buf, RECORD_SIZE);
-	memcpy(buf, s, size);
-	if (write(fd, buf, RECORD_SIZE) == -1)
-	{
-		perror(NULL);
-		return -1;
-	}
-	return (0);
-}
-
-int	record_write_blank(int fd, size_t count)
-{
-	char buf[RECORD_SIZE] = {0};
-	while (count-- > 0)
-	{
-		if (write(fd, buf, RECORD_SIZE) == -1)
-		{
-			perror(NULL);
-			return -1;
-		}
-	}
-	return 0;
-}
-
 int	header_write(int fd, char *file_name, struct stat *statbuf)
 {
 	t_header		header;
@@ -97,22 +58,26 @@ int	header_write(int fd, char *file_name, struct stat *statbuf)
 	return record_write(fd, (char*)&header, sizeof(t_header));
 }
 
-int header_parse(char record[RECORD_SIZE])
+int header_parse(char record[RECORD_SIZE], struct stat *statbuf, t_header *header)
 {
-	t_header	header;
-	mode_t		mode;
-	gid_t		gid;
-	uid_t		uid;
+	unsigned int	actual_checksum;
+	unsigned int	expected_checksum;
+
+	memcpy(header, record, sizeof(t_header));
 
-	memcpy(&header, record, sizeof(t_header));
-	/* sscanf(header.file_mode, "% */
+	actual_checksum = -1;
+	sscanf(header->checksum, "%06o", &actual_checksum);
+	memset(header->checksum, ' ', 8);
+	expected_checksum = 0;
+	for (size_t i = 0; i < sizeof(t_header); i++)
+		expected_checksum += ((uint8_t*)header)[i];
+	if (actual_checksum != expected_checksum)
+		return -1;
 
-	/* sscanf(header.file_mode, "%07o", statbuf->st_mode); */
-	/* sscanf(header.user_id,   "%07o", statbuf->st_uid); */
-	/* sscanf(header.group_id,  "%07o", statbuf->st_gid); */
-    /*  */
-	/* sscanf(header.file_size, "%011lo", statbuf->st_size); */
-    /*  */
-	/* sscanf(header.last_time, "%011lo", statbuf->st_mtime); */
+	sscanf(header->file_mode, "%07o", &statbuf->st_mode);
+	sscanf(header->user_id,   "%07o", &statbuf->st_uid);
+	sscanf(header->group_id,  "%07o", &statbuf->st_gid);
+	sscanf(header->file_size, "%011lo", (long unsigned int*)&statbuf->st_size);
+	sscanf(header->last_time, "%011lo", (long unsigned int*)&statbuf->st_mtime);
 	return 0;
 }
diff --git a/src/record.c b/src/record.c
new file mode 100644
index 0000000..be78978
--- /dev/null
+++ b/src/record.c
@@ -0,0 +1,60 @@
+#include "tar.h"
+
+int	record_write(int fd, char *s, size_t size)
+{
+	char buf[RECORD_SIZE];
+
+	while (size > RECORD_SIZE)
+	{
+		memcpy(buf, s, RECORD_SIZE);
+		s += RECORD_SIZE;
+		size -= RECORD_SIZE;
+		if (write(fd, buf, RECORD_SIZE) == -1)
+		{
+			perror(NULL);
+			return -1;
+		}
+	}
+	bzero(buf, RECORD_SIZE);
+	memcpy(buf, s, size);
+	if (write(fd, buf, RECORD_SIZE) == -1)
+	{
+		perror(NULL);
+		return -1;
+	}
+	return (0);
+}
+
+int	record_write_blank(int fd, size_t count)
+{
+	char buf[RECORD_SIZE] = {0};
+	while (count-- > 0)
+	{
+		if (write(fd, buf, RECORD_SIZE) == -1)
+		{
+			perror(NULL);
+			return -1;
+		}
+	}
+	return 0;
+}
+
+int	record_read(int fd, char record[RECORD_SIZE])
+{
+	int ret = read(fd, record, RECORD_SIZE);
+	if (ret == -1)
+	{
+		perror(NULL);
+		return -1;
+	}
+	if (ret != RECORD_SIZE)
+		return -1;
+	return 0;
+}
+
+static char		g_record_blank[RECORD_SIZE] = {0};
+
+bool	record_is_blank(char record[RECORD_SIZE])
+{
+	return memcmp(record, g_record_blank, RECORD_SIZE) == 0;
+}