wgtpkg-install: choose the port

The installer now chooses a port for an installed application.

This choose is made by consulting the previously installed
applications and by getting the lowest port available in the
range 1024..32767.

Change-Id: Iab4238b4d52447a2d261d87d45bbb02f0b7a35e5
Signed-off-by: José Bollo <jose.bollo@iot.bzh>

2 files changed, 83 insertions, 15 deletions

diff --git a/docs/permissions.md b/docs/permissions.md
index 407fdc2..09f68a3 100644
--- a/docs/permissions.md
+++ b/docs/permissions.md
@@ -14,15 +14,15 @@ framework to keep installed permissions in a database.
 
 The permission names are [URN][URN] of the form:
 
-  urn:AGL:permission:<api>:<level>:<hierarchical-name>
+	urn:AGL:permission:<api>:<level>:<hierarchical-name>
 
 where "AGL" is the NID (the namespace identifier) dedicated to
 AGL (note: a RFC should be produced to standardize this name space).
 
 The permission names are made of NSS (the namespace specific string)
 starting with "permission:" and followed by colon separated
-fields. The 2 first fields are <api> and <level> and the remaining
-fields are grouped to form the <hierarchical-name>.
+fields. The 2 first fields are `<api>` and `<level>` and the remaining
+fields are grouped to form the `<hierarchical-name>`.
 
 	<api> ::= [ <pname> ]
 
@@ -32,30 +32,35 @@ fields are grouped to form the <hierarchical-name>.
 
 	<extra> ::= "-" | "." | "_" | "@"
 
-The field <api> can be made of any valid character for NSS except
+The field `<api>` can be made of any valid character for NSS except
 the characters colon and star (:*). This field designates the api
 providing the permission. This scheme is used to deduce binding requirements
-from permission requirements. The field <api> can be the empty
+from permission requirements. The field `<api>` can be the empty
 string when the permission is defined by the AGL system itself.
-The field <api> if starting with the character "@" represents
+The field `<api>` if starting with the character "@" represents
 a transversal/cross permission not bound to any binding.
 
 	<level> ::= 1*<lower>
 
-The field <level> is made only of letters in lower case.
-The field <level> can only take some predefined values:
-"system", "platform", "partner", "tiers", "owner", "public".
+The field `<level>` is made only of letters in lower case.
+The field `<level>` can only take some predefined values:
+
+ - system
+ - platform
+ - partner
+ - tiers
+ - owner
+ - public
+
+The field `<hierarchical-name>` is made of `<pname>` separated
+by colons.
 
 	<hierarchical-name> ::= <pname> 0*(":" <pname>)
 
-The field <hierarchical-name> is made <pname> separated by
-colons. The names at left are hierarchically grouping the
+The names at left are hierarchically grouping the
 names at right. This hierarchical behaviour is intended to
 be used to request permissions using hierarchical grouping.
 
-Permission's level
-------------------
-
 
 [URN]: https://tools.ietf.org/rfc/rfc2141.txt "RFC 2141: URN Syntax"
 
diff --git a/src/wgtpkg-install.c b/src/wgtpkg-install.c
index 836b136..22b8050 100644
--- a/src/wgtpkg-install.c
+++ b/src/wgtpkg-install.c
@@ -25,6 +25,8 @@
 #include <assert.h>
 #include <unistd.h>
 #include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
 #include <sys/stat.h>
 
 #include "verbose.h"
@@ -40,12 +42,68 @@
 #include "secmgr-wrap.h"
 #include "utils-dir.h"
 #include "wgtpkg-unit.h"
+#include "utils-systemd.h"
+#include "utils-file.h"
 
 static const char* exec_type_strings[] = {
 	"application/x-executable",
 	"application/vnd.agl.native"
 };
 
+static const char key_http_port[] = "X-AFM--http-port";
+
+static int get_port_cb(void *closure, const char *name, const char *path, int isuser)
+{
+	char *iter;
+	char *content;
+	size_t length;
+	int rc, p;
+
+	/* reads the file */
+	rc = getfile(path, &content, &length);
+	if (rc < 0)
+		return rc;
+
+	/* process the file */
+	iter = strstr(content, key_http_port);
+	while (iter) {
+		iter += sizeof key_http_port - 1;
+		while(*iter && *iter != '=' && *iter != '\n')
+			iter++;
+		if (*iter == '=') {
+			while(*++iter == ' ');
+			p = atoi(iter);
+			if (p >= 0 && p < 32768)
+				((uint32_t*)closure)[p >> 5] |= (uint32_t)1 << (p & 31);
+		}
+		iter = strstr(iter, key_http_port);
+	}
+	free(content);
+	return 0;
+}
+
+static int get_port()
+{
+	int rc;
+	uint32_t ports[1024]; /* 1024 * 32 = 32768 */
+
+	memset(ports, 0, sizeof ports);
+	rc = systemd_unit_list(0, get_port_cb, &ports);
+	if (rc >= 0) {
+		rc = systemd_unit_list(1, get_port_cb, ports);
+		if (rc >= 0) {
+			for (rc = 1024 ; rc < 32768 && !~ports[rc >> 5] ; rc += 32);
+			if (rc == 32768) {
+				errno = EADDRNOTAVAIL;
+				rc = -1;
+			} else {
+				while (1 & (ports[rc >> 5] >> (rc & 31))) rc++;
+			}
+		}
+	}
+	return rc;
+}
+
 static int check_defined(const void *data, const char *name)
 {
 	if (data)
@@ -294,6 +352,7 @@ struct wgt_info *install_widget(const char *wgtfile, const char *root, int force
 	struct wgt_info *ifo;
 	const struct wgt_desc *desc;
 	char installdir[PATH_MAX];
+	int port;
 
 	NOTICE("-- INSTALLING widget %s to %s --", wgtfile, root);
 
@@ -334,7 +393,11 @@ struct wgt_info *install_widget(const char *wgtfile, const char *root, int force
 	if (install_exec_flag(desc))
 		goto error4;
 
-	if (unit_install(ifo, installdir, FWK_ICON_DIR, 1234/*TODO*/))
+	port = get_port();
+	if (port < 0)
+		goto error4;
+
+	if (unit_install(ifo, installdir, FWK_ICON_DIR, port))
 		goto error4;
 
 	file_reset();