opk: Extract control files

4 files changed, 131 insertions, 23 deletions

diff --git a/configure.ac b/configure.ac
index 38c62c2..fc76e4e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -44,8 +44,9 @@ funcs_missing=false
 AC_CHECK_FUNCS(
 	[\
 		fclose feof ferror fopen fprintf fputs fread free fwrite \
-		localtime malloc memcmp memcpy memset printf puts snprintf \
-		sprintf strcmp strcpy strftime strlen strncpy strtol
+		localtime malloc memcmp memcpy memset mkdir printf puts \
+		snprintf sprintf stat strcmp strcpy strftime strlen strncpy \
+		strtol
 	],
 	[],
 	[funcs_missing=true])
diff --git a/src/main.c b/src/main.c
index 2c3fa87..08be875 100644
--- a/src/main.c
+++ b/src/main.c
@@ -36,10 +36,16 @@
 
 extern const char *PACKAGE_VERSION_GIT;
 
-const char *_optstring = "f:F:lLhV";
+const char *_optstring = "c:f:F:lLhV";
 #ifdef HAVE_GETOPT_LONG
 struct option _longopts[] = {
 	{
+		.name    = "control-dir",
+		.has_arg = 1,
+		.flag    = NULL,
+		.val     = 'c',
+	},
+	{
 		.name    = "control-file",
 		.has_arg = 1,
 		.flag    = NULL,
@@ -81,10 +87,11 @@ struct option _longopts[] = {
 static void
 _help(const char *program_name)
 {
-	printf(_("Usage: %s [-f CONTROL-FILE] [-F DATA-FILE] [-l] [-L] "
-				"PACKAGE\n"), program_name);
+	printf(_("Usage: %s [-c CONTROL-DIR] [-f CONTROL-FILE] [-F DATA-FILE] "
+				"[-l] [-L] PACKAGE\n"), program_name);
 #ifdef HAVE_GETOPT_LONG
 	puts(_("Options:\n"
+"  -c, --control-dir=CONTROL-DIR    Extract control files into CONTROL-DIR.\n"
 "  -f, --control-file=CONTROL-FILE  Print the contents of the named control "
                                    "file.\n"
 "                                   If this option is given multiple times, the"
@@ -210,6 +217,9 @@ main(int argc, char *argv[])
 	while ((opt = getopt(argc, argv, _optstring)) != -1) {
 #endif
 		switch(opt) {
+			case 'c':
+				opkg_opk_opk_control_dir(opk, optarg);
+				break;
 			case 'f':
 				if (opt_l > 0) {
 					_opt_mutex(program_name, 'f', 'l');
diff --git a/src/opk.c b/src/opk.c
index db35cab..62b09f2 100644
--- a/src/opk.c
+++ b/src/opk.c
@@ -21,6 +21,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
 #include <time.h>
 #include "defs.h"
 #include "gzip.h"
@@ -41,6 +42,7 @@ struct opkg_opk_opk {
 	struct _opkg_opk_opk_seek_name *print_data_tail;
 	int                             list_control;
 	int                             list_data;
+	const char                     *control_dir;
 	FILE                           *file;
 	char                            file_buffer[8192];
 	struct opkg_opk_gzip           *outer_gzip;
@@ -66,6 +68,7 @@ opkg_opk_opk_init(void)
 	opk->print_data_tail    = NULL;
 	opk->list_control       = 0;
 	opk->list_data          = 0;
+	opk->control_dir        = NULL;
 	opk->previously_printed = 0;
 
 	return opk;
@@ -128,6 +131,13 @@ opkg_opk_opk_list_data(struct opkg_opk_opk *opk)
 	return OPKG_OPK_OK;
 }
 
+int
+opkg_opk_opk_control_dir(struct opkg_opk_opk *opk, const char *dir)
+{
+	opk->control_dir = dir;
+	return OPKG_OPK_OK;
+}
+
 static int
 _opkg_opk_opk_file_read(void *user_data, char **buffer, size_t *size)
 {
@@ -213,58 +223,116 @@ _opkg_opk_opk_check_name(const char *member_name,
 static int
 _opkg_opk_opk_read_control(struct opkg_opk_opk *opk)
 {
+	struct stat                     stat_buf;
+	char                           *path;
 	struct opkg_opk_ustar_member   *member;
 	int                             ret_list;
+	FILE                           *fp;
+	int                             print;
 	int                             ret_read;
 	char                           *buffer;
 	size_t                          size;
 	struct _opkg_opk_opk_seek_name *seek_name;
 
-	if (opk->list_control == 0 && opk->print_control_head == NULL) {
+	if (opk->control_dir != NULL) {
+		if (stat(opk->control_dir, &stat_buf) == 0) {
+			if (!S_ISDIR(stat_buf.st_mode)) {
+				fputs(_("Error: Cannot create control directory"
+							"\n"), stderr);
+				return OPKG_OPK_ERROR;
+			}
+		} else if (mkdir(opk->control_dir, 0755) != 0) {
+			fputs(_("Error: Cannot create control directory"
+						"\n"), stderr);
+			return OPKG_OPK_ERROR;
+		}
+		path = malloc(strlen(opk->control_dir) +
+				OPKG_OPK_USTAR_NAME_SIZE + 1);
+		if (path == NULL) {
+			return OPKG_OPK_ERROR;
+		}
+	} else if (opk->list_control == 0 && opk->print_control_head == NULL) {
 		/* Not listing or printing any control files. */
 		return OPKG_OPK_OK;
 	}
 
 	if (_opkg_opk_opk_init_inner(opk) != OPKG_OPK_OK) {
+		if (opk->control_dir != NULL) {
+			free(path);
+		}
 		return OPKG_OPK_ERROR;
 	}
 
 	while ((ret_list = opkg_opk_ustar_list(opk->inner_ustar, &member)) ==
 			OPKG_OPK_OK) {
-		if (opk->list_control > 0) {
-			buffer = member->name;
-			if (buffer[0] == '.' && buffer[1] == '/') {
-				buffer += 2;
+		/* Remove leading "./" if present and skip if nothing's left. */
+		buffer = member->name;
+		if (buffer[0] == '.' && buffer[1] == '/') {
+			buffer += 2;
+		}
+		if (buffer[0] == '\0') {
+			free(member);
+			continue;
+		}
+
+		/* Open file for extraction. */
+		if (opk->control_dir != NULL) {
+			if (sprintf(path, "%s/%s", opk->control_dir,
+						member->name) <= 0) {
+				free(member);
+				_opkg_opk_opk_free_inner(opk);
+				free(path);
+				return OPKG_OPK_ERROR;
 			}
-			if (buffer[0] != '\0') {
-				puts(buffer);
-				opk->previously_printed = 1;
+			fp = fopen(path, "wb");
+			if (fp == NULL) {
+				fputs(_("Error: Failed to extract control file"
+							"\n"), stderr);
+				free(member);
+				_opkg_opk_opk_free_inner(opk);
+				free(path);
+				return OPKG_OPK_ERROR;
 			}
 		}
 
-		if (opk->print_control_head == NULL) {
-			free(member);
-			continue;
+		if (opk->list_control > 0) {
+			puts(buffer);
+			opk->previously_printed = 1;
 		}
-		if (_opkg_opk_opk_check_name(member->name,
+
+		if (opk->print_control_head != NULL &&
+				_opkg_opk_opk_check_name(member->name,
 					&opk->print_control_head,
-					&opk->print_control_tail) !=
+					&opk->print_control_tail) ==
 				OPKG_OPK_OK) {
-			/* Name not requested for printing. */
-			free(member);
-			continue;
+			/* Name requested for printing. */
+			print = 1;
+		} else {
+			print = 0;
 		}
 		free(member);
-		if (opk->previously_printed == 1) {
+		if (print == 1 && opk->previously_printed == 1) {
 			puts("");
 		}
 		while ((ret_read = opkg_opk_ustar_read(opk->inner_ustar,
 						&buffer, &size)) == OPKG_OPK_OK)
 		{
-			if (fwrite(buffer, 1, size, stdout) != size) {
+			if (print == 1 && fwrite(buffer, 1, size, stdout) !=
+					size) {
 				fputs(_("Error: Failed to print control file\n")
 						, stderr);
 				_opkg_opk_opk_free_inner(opk);
+				if (opk->control_dir != NULL) {
+					free(path);
+				}
+				return OPKG_OPK_ERROR;
+			}
+			if (opk->control_dir != NULL && fwrite(buffer, 1, size,
+						fp) != size) {
+				fputs(_("Error: Failed to write control file\n")
+						, stderr);
+				_opkg_opk_opk_free_inner(opk);
+				free(path);
 				return OPKG_OPK_ERROR;
 			}
 		}
@@ -272,9 +340,25 @@ _opkg_opk_opk_read_control(struct opkg_opk_opk *opk)
 			fputs(_("Error: Failed to read control file\n"),
 					stderr);
 			_opkg_opk_opk_free_inner(opk);
+			if (opk->control_dir != NULL) {
+				free(path);
+			}
 			return OPKG_OPK_ERROR;
 		}
 		opk->previously_printed = 1;
+
+		/* Close file for extraction. */
+		if (opk->control_dir != NULL) {
+			if (fclose(fp) != 0) {
+				_opkg_opk_opk_free_inner(opk);
+				free(path);
+				return OPKG_OPK_ERROR;
+			}
+		}
+	}
+	if (opk->control_dir != NULL) {
+		/* Done with path buffer. */
+		free(path);
 	}
 	if (ret_list == OPKG_OPK_ERROR) {
 		fputs(_("Error: Failed to list control files\n"), stderr);
@@ -337,6 +421,7 @@ _opkg_opk_opk_read_data(struct opkg_opk_opk *opk)
 	size_max      = 0;
 	while ((ret = opkg_opk_ustar_list(opk->inner_ustar, &member)) ==
 			OPKG_OPK_OK) {
+		/* If listing, link members and update max column widths. */
 		if (opk->list_data > 0) {
 			if (head == NULL) {
 				head = member;
diff --git a/src/opk.h b/src/opk.h
index 4d70aa2..049953f 100644
--- a/src/opk.h
+++ b/src/opk.h
@@ -80,6 +80,18 @@ int
 opkg_opk_opk_list_data(struct opkg_opk_opk *opk);
 
 /*
+ * Sets the directory into which to extract control files.  The directory (but
+ * not its ancestors) will be created if it doesn't exist.
+ * Parameters:
+ * - opk: Package structure.
+ * - dir: Directory.
+ * Returns:
+ * - OPKG_OPK_OK.
+ */
+int
+opkg_opk_opk_control_dir(struct opkg_opk_opk *opk, const char *dir);
+
+/*
  * Performs the configured read actions.
  * Parameters:
  * - file_name: Package's file name.