Add install command

Signed-off-by: David Oberhollenzer <goliath@infraroot.at>

Makefile.am

@@ -33,6 +33,11 @@ pkg_SOURCES += main/cmd/pack/desc.c main/cmd/pack/write_hdr.c
 pkg_SOURCES += main/cmd/dump/dump.c main/cmd/dump/dump.h main/cmd/dump/dump_toc.c
 pkg_SOURCES += main/cmd/dump/dump_header.c
 
+# install command
+pkg_SOURCES += main/cmd/install/collect.c main/cmd/install/install.c
+pkg_SOURCES += main/cmd/install/install.h main/cmd/install/pkglist.c
+pkg_SOURCES += main/cmd/install/tsort.c
+
 # unpack command
 pkg_SOURCES += main/cmd/unpack.c
 

include/pkgreader.h

@@ -7,6 +7,8 @@ typedef struct pkg_reader_t pkg_reader_t;
 
 pkg_reader_t *pkg_reader_open(const char *path);
 
+pkg_reader_t *pkg_reader_open_repo(int dirfd, const char *name);
+
 void pkg_reader_close(pkg_reader_t *reader);
 
 int pkg_reader_get_next_record(pkg_reader_t *reader);

main/cmd/install/collect.c

@@ -0,0 +1,67 @@
+#include "install.h"
+
+int collect_dependencies(int repofd, struct pkg_dep_list *list)
+{
+	struct pkg_dep_node *it;
+	pkg_dependency_t dep;
+	uint8_t buffer[257];
+	pkg_reader_t *rd;
+	pkg_header_t hdr;
+	size_t i;
+	int ret;
+
+	for (it = list->head; it != NULL; it = it->next) {
+		rd = pkg_reader_open_repo(repofd, it->name);
+		if (rd == NULL)
+			return -1;
+
+		ret = pkg_reader_read_payload(rd, &hdr, sizeof(hdr));
+		if (ret < 0)
+			goto fail;
+		if ((size_t)ret < sizeof(hdr))
+			goto fail_trunc;
+
+		it->num_deps = le16toh(hdr.num_depends);
+		it->deps = calloc(sizeof(it->deps[0]), it->num_deps);
+		if (it->deps == NULL)
+			goto fail_oom;
+
+		for (i = 0; i < it->num_deps; ++i) {
+			ret = pkg_reader_read_payload(rd, &dep, sizeof(dep));
+			if (ret < 0)
+				goto fail;
+			if ((size_t)ret < sizeof(hdr))
+				goto fail_trunc;
+
+			ret = pkg_reader_read_payload(rd, buffer,
+						      dep.name_length);
+			if (ret < 0)
+				goto fail;
+			if ((size_t)ret < dep.name_length)
+				goto fail_trunc;
+
+			buffer[dep.name_length] = '\0';
+
+			it->deps[i] = find_pkg(list, (char *)buffer);
+			if (it->deps[i] == NULL) {
+				it->deps[i] = append_pkg(list, (char *)buffer);
+				if (it->deps[i] == NULL)
+					goto fail;
+			}
+		}
+
+		pkg_reader_close(rd);
+	}
+
+	return 0;
+fail_trunc:
+	fprintf(stderr, "%s: truncated header record\n",
+		pkg_reader_get_filename(rd));
+	goto fail;
+fail_oom:
+	fputs("out of memory\n", stderr);
+	goto fail;
+fail:
+	pkg_reader_close(rd);
+	return -1;
+}

main/cmd/install/install.c

@@ -0,0 +1,137 @@
+#include "install.h"
+
+static const struct option long_opts[] = {
+	{ "root", required_argument, NULL, 'r' },
+	{ "no-chown", required_argument, NULL, 'o' },
+	{ "no-chmod", required_argument, NULL, 'm' },
+	{ "repo-dir", required_argument, NULL, 'R' },
+	{ NULL, 0, NULL, 0 },
+};
+
+static const char *short_opts = "R:r:om";
+
+static int unpack_packages(int repofd, int rootfd, int flags,
+			   struct pkg_dep_list *list)
+{
+	struct pkg_dep_node *it;
+	pkg_reader_t *rd;
+
+	for (it = list->head; it != NULL; it = it->next) {
+		rd = pkg_reader_open_repo(repofd, it->name);
+		if (rd == NULL)
+			return -1;
+
+		if (pkg_unpack(rootfd, flags, rd)) {
+			pkg_reader_close(rd);
+			return -1;
+		}
+
+		pkg_reader_close(rd);
+	}
+
+	return 0;
+}
+
+static int cmd_install(int argc, char **argv)
+{
+	int i, rootfd = AT_FDCWD, repofd = AT_FDCWD, flags = 0;
+	struct pkg_dep_list list;
+	int ret = EXIT_FAILURE;
+
+	memset(&list, 0, sizeof(list));
+
+	for (;;) {
+		i = getopt_long(argc, argv, short_opts, long_opts, NULL);
+		if (i == -1)
+			break;
+
+		switch (i) {
+		case 'R':
+			if (repofd != AT_FDCWD) {
+				fputs("repo specified more than once\n",
+				      stderr);
+				tell_read_help(argv[0]);
+				goto out;
+			}
+			repofd = open(optarg, O_RDONLY | O_DIRECTORY);
+			if (repofd < 0) {
+				perror(optarg);
+				goto out;
+			}
+			break;
+		case 'r':
+			if (rootfd != AT_FDCWD) {
+				fputs("root specified more than once\n",
+				      stderr);
+				tell_read_help(argv[0]);
+				goto out;
+			}
+
+			if (mkdir_p(optarg))
+				goto out;
+
+			rootfd = open(optarg, O_RDONLY | O_DIRECTORY);
+			if (rootfd < 0) {
+				perror(optarg);
+				goto out;
+			}
+			break;
+		case 'o':
+			flags |= UNPACK_NO_CHOWN;
+			break;
+		case 'm':
+			flags |= UNPACK_NO_CHMOD;
+			break;
+		default:
+			tell_read_help(argv[0]);
+			goto out;
+		}
+	}
+
+	for (i = optind; i < argc; ++i) {
+		if (append_pkg(&list, argv[i]) == NULL)
+			goto out;
+	}
+
+	if (collect_dependencies(repofd, &list))
+		goto out;
+
+	if (sort_by_dependencies(&list))
+		goto out;
+
+	if (unpack_packages(repofd, rootfd, flags, &list))
+		goto out;
+
+	ret = EXIT_SUCCESS;
+out:
+	if (rootfd != AT_FDCWD)
+		close(rootfd);
+	if (repofd != AT_FDCWD)
+		close(repofd);
+	pkg_list_cleanup(&list);
+	return ret;
+}
+
+static command_t install = {
+	.cmd = "install",
+	.usage = "[OPTIONS...] PACKAGES...",
+	.s_desc = "install packages and their dependencies",
+	.l_desc =
+"The install command fetches a number of packages from a repository directory\n"
+"by name and extracts them to a specified root directory. Dependencies of the\n"
+"packages are evaluated and also installed.\n"
+"\n"
+"Possible options:\n"
+"  --repo-dir, -R <path>  Specify the input repository path to fetch the\n"
+"                         packages from.\n"
+"  --root, -r <path>      A root directory to unpack the package. Defaults\n"
+"                         to the current working directory if not set.\n"
+"  --no-chown, -o         Do not change ownership of the extracted data.\n"
+"                         Keep the uid/gid of the user who runs the program.\n"
+"  --no-chmod, -m         Do not change permission flags of the extarcted\n"
+"                         data. Use 0644 for all files and 0755 for all\n"
+"                         directories.\n",
+	.run_cmd = cmd_install,
+};
+
+REGISTER_COMMAND(install)

main/cmd/install/install.h

@@ -0,0 +1,44 @@
+#ifndef INSTALL_H
+#define INSTALL_H
+
+#include <getopt.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdio.h>
+#include <fcntl.h>
+
+#include "pkgreader.h"
+#include "command.h"
+#include "pkgio.h"
+#include "util.h"
+
+struct pkg_dep_node {
+	char *name;
+
+	/* num dependencies == number of outgoing edges */
+	size_t num_deps;
+
+	/* direct dependencies == array of outgoing edges */
+	struct pkg_dep_node **deps;
+
+	/* linked list pointer */
+	struct pkg_dep_node *next;
+};
+
+struct pkg_dep_list {
+	struct pkg_dep_node *head;
+	struct pkg_dep_node *tail;
+};
+
+struct pkg_dep_node *append_pkg(struct pkg_dep_list *list, const char *name);
+
+struct pkg_dep_node *find_pkg(struct pkg_dep_list *list, const char *name);
+
+void pkg_list_cleanup(struct pkg_dep_list *list);
+
+int collect_dependencies(int repofd, struct pkg_dep_list *list);
+
+int sort_by_dependencies(struct pkg_dep_list *list);
+
+#endif /* INSTALL_H */

main/cmd/install/pkglist.c

@@ -0,0 +1,51 @@
+#include "install.h"
+
+struct pkg_dep_node *append_pkg(struct pkg_dep_list *list, const char *name)
+{
+	struct pkg_dep_node *new = calloc(1, sizeof(*new));
+
+	if (new == NULL)
+		goto fail_oom;
+
+	new->name = strdup(name);
+	if (new->name == NULL)
+		goto fail_oom;
+
+	if (list->tail == NULL) {
+		list->head = list->tail = new;
+	} else {
+		list->tail->next = new;
+		list->tail = new;
+	}
+	return new;
+fail_oom:
+	fputs("out of memory\n", stderr);
+	free(new);
+	return NULL;
+}
+
+struct pkg_dep_node *find_pkg(struct pkg_dep_list *list, const char *name)
+{
+	struct pkg_dep_node *it = list->head;
+
+	while (it != NULL && strcmp(it->name, name) != 0)
+		it = it->next;
+
+	return it;
+}
+
+void pkg_list_cleanup(struct pkg_dep_list *list)
+{
+	struct pkg_dep_node *node;
+
+	while (list->head != NULL) {
+		node = list->head;
+		list->head = node->next;
+
+		free(node->deps);
+		free(node->name);
+		free(node);
+	}
+
+	list->tail = NULL;
+}

main/cmd/install/tsort.c

@@ -0,0 +1,69 @@
+#include "install.h"
+
+int sort_by_dependencies(struct pkg_dep_list *list)
+{
+	struct pkg_dep_node *it, *prev, *pkg;
+	struct pkg_dep_list result;
+	size_t i;
+
+	result.head = NULL;
+	result.tail = NULL;
+
+	while (list->head != NULL) {
+		/* find node with no outgoing edges */
+		prev = NULL;
+		it = list->head;
+
+		while (it != NULL && it->num_deps != 0) {
+			prev = it;
+			it = it->next;
+		}
+
+		if (it == NULL) {
+			fputs("cycle detected in dependency graph\n", stderr);
+			pkg_list_cleanup(&result);
+			return -1;
+		}
+
+		/* remove from graph */
+		if (prev == NULL) {
+			list->head = it->next;
+		} else {
+			prev->next = it->next;
+		}
+
+		if (it == list->tail)
+			list->tail = prev;
+
+		/* remove edges pointing to the package */
+		pkg = it;
+
+		for (it = list->head; it != NULL; it = it->next) {
+			for (i = 0; i < it->num_deps; ++i) {
+				if (it->deps[i] == pkg) {
+					it->deps[i] =
+						it->deps[it->num_deps - 1];
+					it->num_deps -= 1;
+					--i;
+				}
+			}
+
+			if (it->num_deps == 0 && it->deps != NULL) {
+				free(it->deps);
+				it->deps = NULL;
+			}
+		}
+
+		/* append to list */
+		if (result.tail == NULL) {
+			result.head = result.tail = pkg;
+		} else {
+			result.tail->next = pkg;
+			result.tail = pkg;
+		}
+	}
+
+	list->head = result.head;
+	list->tail = result.tail;
+	return 0;
+}

main/pkgreader.c

@@ -5,6 +5,7 @@
 #include <stdio.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <ctype.h>
 
 #include "util.h"
 #include "pkgreader.h"
@@ -118,7 +119,7 @@ fail_comp:
 	return -1;
 }
 
-pkg_reader_t *pkg_reader_open(const char *path)
+static pkg_reader_t *pkg_reader_openat(int dirfd, const char *path)
 {
 	pkg_reader_t *rd = calloc(1, sizeof(*rd));
 	int ret;
@@ -129,7 +130,7 @@ pkg_reader_t *pkg_reader_open(const char *path)
 	}
 
 	rd->path = path;
-	rd->fd = open(path, O_RDONLY);
+	rd->fd = openat(dirfd, path, O_RDONLY);
 	if (rd->fd < 0) {
 		perror(path);
 		free(rd);
@@ -150,6 +151,31 @@ fail:
 	return NULL;
 }
 
+pkg_reader_t *pkg_reader_open(const char *path)
+{
+	return pkg_reader_openat(AT_FDCWD, path);
+}
+
+pkg_reader_t *pkg_reader_open_repo(int dirfd, const char *name)
+{
+	char *fname;
+	size_t i;
+
+	for (i = 0; name[i] != '\0'; ++i) {
+		if (!isalnum(name[i]) && name[i] != '_' && name[i] != '-') {
+			fprintf(stderr,
+				"illegal characters in package name '%s'\n",
+				name);
+			return NULL;
+		}
+	}
+
+	fname = alloca(strlen(name) + 5);
+	sprintf(fname, "%s.pkg", name);
+
+	return pkg_reader_openat(dirfd, fname);
+}
+
 void pkg_reader_close(pkg_reader_t *rd)
 {
 	if (rd->stream != NULL)