Implemented support for pre-remove and post-install messages.

Close #44

NEWS

@@ -1,5 +1,11 @@
 xbps-0.38 (???):
 
+ * Implemented support for post-install and pre-remove messages, as explained
+   in issue #44 https://github.com/voidlinux/xbps/issues/44.
+
+   xbps-create(8): will read the {INSTALL,REMOVE}.msg files and will add its contents
+   into the `{install,remove}-msg` data objects into its metadata plist file.
+
  * xbps-install(8): added support to list packages that will be downloaded, if those
    were available in a remote repository and were not in the cache directory.
 

bin/xbps-create/main.c

@@ -160,6 +160,54 @@ out:
 	xbps_object_release(array);
 }
 
+static void
+process_file(const char *file, const char *key)
+{
+	void *blob;
+	FILE *f;
+	struct stat st;
+	size_t len;
+	xbps_data_t data;
+
+	if ((f = fopen(file, "r")) == NULL)
+		return;
+
+	if (fstat(fileno(f), &st) == -1) {
+		fclose(f);
+		die("lstat %s", file);
+	}
+
+	if (S_ISREG(st.st_mode) == 0) {
+		fclose(f);
+		return;
+	}
+
+	len = st.st_size;
+
+	if ((blob = malloc(len)) == NULL) {
+	        fclose(f);
+		die("malloc %s", file);
+	}
+
+	if (fread(blob, len, 1, f) != len) {
+		if (ferror(f)) {
+			fclose(f);
+			die("fread %s", file);
+		}
+	}
+	fclose(f);
+
+	if ((data = xbps_data_create_data(blob, len)) == NULL)
+		die("xbps_data_create_data %s", file);
+
+	free(blob);
+
+	if (!xbps_dictionary_set(pkg_propsd, key, data))
+		die("xbps_dictionary_set %s", key);
+
+	xbps_object_release(data);
+}
+
 static bool
 entry_is_conf_file(const char *file)
 {
@@ -190,6 +238,8 @@ ftw_cb(const char *fpath, const struct stat *sb, int type, struct FTW *ftwbuf _u
 
 	/* Ignore metadata files generated by xbps-src and destdir */
 	if ((strcmp(fpath, ".") == 0) ||
+	    (strcmp(fpath, "./INSTALL.msg") == 0) ||
+	    (strcmp(fpath, "./REMOVE.msg") == 0) ||
 	    (strcmp(fpath, "./props.plist") == 0) ||
 	    (strcmp(fpath, "./files.plist") == 0) ||
 	    (strcmp(fpath, "./flist") == 0) ||
@@ -754,6 +804,10 @@ main(int argc, char **argv)
 
 	if (chdir(destdir) == -1)
 		die("cannot chdir() to destdir %s:", destdir);
+
+	/* Optional INSTALL/REMOVE messages */
+	process_file("INSTALL.msg", "install-msg");
+	process_file("REMOVE.msg", "remove-msg");
 	/*
 	 * Process XBPS_PKGFILES metadata file.
 	 */

bin/xbps-install/state_cb.c

@@ -133,6 +133,9 @@ state_cb(struct xbps_state_cb_data *xscd, void *cbdata _unused)
 		printf("Fingerprint: %s\n", xscd->arg);
 		rv = yesno("Do you want to import this public key?");
 		break;
+	case XBPS_STATE_SHOW_INSTALL_MSG:
+		printf("%s: post-install message:\n%s", xscd->arg, xscd->desc);
+		break;
 	/* errors */
 	case XBPS_STATE_UNPACK_FAIL:
 	case XBPS_STATE_UPDATE_FAIL:

bin/xbps-remove/main.c

@@ -91,6 +91,9 @@ state_cb_rm(struct xbps_state_cb_data *xscd, void *cbdata _unused)
 			    xscd->xhp->rootdir);
 		}
 		break;
+	case XBPS_STATE_SHOW_REMOVE_MSG:
+		printf("%s: pre-remove message:\n%s", xscd->arg, xscd->desc);
+		break;
 	/* errors */
 	case XBPS_STATE_REMOVE_FAIL:
 		xbps_error_printf("%s\n", xscd->desc);

include/xbps.h.in

@@ -48,7 +48,7 @@
  *
  * This header documents the full API for the XBPS Library.
  */
-#define XBPS_API_VERSION	"20140713"
+#define XBPS_API_VERSION	"20140727"
 
 #ifndef XBPS_VERSION
  #define XBPS_VERSION		"UNSET"
@@ -276,6 +276,8 @@ extern "C" {
  * - XBPS_STATE_REPOSYNC_FAIL: syncing remote repositories has failed.
  * - XBPS_STATE_REPO_KEY_IMPORT: repository is signed and needs to import pubkey.
  * - XBPS_STATE_INVALID_DEP: package has an invalid dependency.
+ * - XBPS_STATE_SHOW_INSTALL_MSG: package must show a post-install message.
+ * - XBPS_STATE_SHOW_REMOVE_MSG: package must show a pre-remove message.
  */
 typedef enum xbps_state {
 	XBPS_STATE_UNKNOWN = 0,
@@ -315,7 +317,9 @@ typedef enum xbps_state {
 	XBPS_STATE_REPOSYNC_FAIL,
 	XBPS_STATE_CONFIGURE_DONE,
 	XBPS_STATE_REPO_KEY_IMPORT,
-	XBPS_STATE_INVALID_DEP
+	XBPS_STATE_INVALID_DEP,
+	XBPS_STATE_SHOW_INSTALL_MSG,
+	XBPS_STATE_SHOW_REMOVE_MSG
 } xbps_state_t;
 
 /**

lib/package_configure.c

@@ -81,7 +81,11 @@ xbps_configure_pkg(struct xbps_handle *xhp,
 		   bool update)
 {
 	xbps_dictionary_t pkgd, pkgmetad;
-	char *pkgname, *plist;
+	xbps_data_t imsg;
+	FILE *f = NULL;
+	const void *data = NULL;
+	size_t len;
+	char *buf = NULL, *pkgname, *plist;
 	int rv = 0;
 	pkg_state_t state = 0;
 
@@ -161,10 +165,41 @@ xbps_configure_pkg(struct xbps_handle *xhp,
 		    pkgver, strerror(rv));
 		return rv;
 	}
-	xbps_object_release(pkgmetad);
-
 	if (rv == 0)
 		xbps_set_cb_state(xhp, XBPS_STATE_CONFIGURE_DONE, 0, pkgver, NULL);
 
+	/* show install-msg if exists */
+	imsg = xbps_dictionary_get(pkgmetad, "install-msg");
+	if (xbps_object_type(imsg) != XBPS_TYPE_DATA)
+		goto out;
+
+	data = xbps_data_data_nocopy(imsg);
+	len = xbps_data_size(imsg);
+	if ((f = fmemopen(__UNCONST(data), len, "r")) == NULL) {
+		rv = errno;
+		xbps_dbg_printf(xhp, "[configure] %s: fmemopen %s\n", pkgver, strerror(rv));
+		goto out;
+	};
+	buf = malloc(len);
+	assert(buf);
+	if (fread(buf, len, 1, f) != len) {
+		if (ferror(f)) {
+			rv = errno;
+			xbps_dbg_printf(xhp, "[configure] %s: fread %s\n", pkgver, strerror(rv));
+			fclose(f);
+			free(buf);
+			goto out;
+		}
+	}
+	/* terminate buffer and notify client to show the post-install message */
+	buf[len] = '\0';
+	xbps_set_cb_state(xhp, XBPS_STATE_SHOW_INSTALL_MSG, 0, pkgver, "%s", buf);
+	fclose(f);
+	free(buf);
+
+out:
+	if (pkgmetad != NULL)
+		xbps_object_release(pkgmetad);
+
 	return rv;
 }

lib/package_remove.c

@@ -256,9 +256,11 @@ xbps_remove_pkg(struct xbps_handle *xhp, const char *pkgver, bool update)
 	if (state == XBPS_PKG_STATE_HALF_REMOVED)
 		goto purge;
 	/*
-	 * Run the pre remove action.
+	 * Run the pre remove action and show pre-remove message if exists.
 	 */
 	if (pkgd) {
+		xbps_data_t rmsg;
+
 		rv = xbps_pkg_exec_script(xhp, pkgd, "remove-script",
 		    "pre", update);
 		if (rv != 0) {
@@ -269,6 +271,38 @@ xbps_remove_pkg(struct xbps_handle *xhp, const char *pkgver, bool update)
 			    pkgver, strerror(rv));
 			goto out;
 		}
+		/* show remove-msg if exists */
+		rmsg = xbps_dictionary_get(pkgd, "remove-msg");
+		if (xbps_object_type(rmsg) == XBPS_TYPE_DATA) {
+			FILE *f;
+			const void *data;
+			char *buf;
+			size_t len;
+
+			data = xbps_data_data_nocopy(rmsg);
+			len = xbps_data_size(rmsg);
+			if ((f = fmemopen(__UNCONST(data), len, "r")) == NULL) {
+				rv = errno;
+				xbps_dbg_printf(xhp, "[remove] %s: fmemopen %s\n", pkgver, strerror(rv));
+				goto out;
+			};
+			buf = malloc(len);
+			assert(buf);
+			if (fread(buf, len, 1, f) != len) {
+				if (ferror(f)) {
+					rv = errno;
+					xbps_dbg_printf(xhp, "[remove] %s: fread %s\n", pkgver, strerror(rv));
+					free(buf);
+					fclose(f);
+					goto out;
+				}
+			}
+			/* terminate buffer and notify client to show the pre-remove message */
+			buf[len] = '\0';
+			xbps_set_cb_state(xhp, XBPS_STATE_SHOW_REMOVE_MSG, 0, pkgver, "%s", buf);
+			free(buf);
+			fclose(f);
+		}
 	}
 	/*
 	 * If updating a package, we just need to execute the current