pong and pongd working (with C bindings)

build.zig

@@ -70,7 +70,7 @@ pub fn build(b: *std.Build) void {
     dynamic_lib.root_module.link_libc = true;
     b.installArtifact(dynamic_lib);
 
-    // pong service using the c client.
+    // pong client using the c client.
     const pong_with_c_bindings = b.addExecutable(.{
         .name = "pong-with-c-bindings", // name of the executable
         .root_module = b.createModule(.{
@@ -96,12 +96,26 @@ pub fn build(b: *std.Build) void {
     // Statically link the executable to the library.
     pong_with_c_bindings.linkLibrary(static_lib);
 
+    // pong service using the c client.
+    const pongd_with_c_bindings = b.addExecutable(.{
+        .name = "pongd-with-c-bindings", // name of the executable
+        .root_module = b.createModule(.{
+            .root_source_file = b.path("src/examples/pongd-with-c-bindings.zig"),
+            .target = target,
+            .optimize = optimize,
+
+            // Again, no need for external modules to import.
+        }),
+    });
+    b.installArtifact(pongd_with_c_bindings);
+    pongd_with_c_bindings.linkLibrary(static_lib);
+
     // This creates a top level step. Top level steps have a name and can be
     // invoked by name when running `zig build` (e.g. `zig build run`).
     // This will evaluate the `run` step rather than the default step.
     // For a top level step to actually do something, it must depend on other
     // steps (e.g. a Run step, as we will see in a moment).
-    const run_step = b.step("run-pong", "Run the pong client");
+    const run_pong_with_c_bindings_step = b.step("run-pong", "Run the pong client");
 
     // This creates a RunArtifact step in the build graph. A RunArtifact step
     // invokes an executable compiled by Zig. Steps will only be executed by the
@@ -109,17 +123,17 @@ pub fn build(b: *std.Build) void {
     // or if another step depends on it, so it's up to you to define when and
     // how this Run step will be executed. In our case we want to run it when
     // the user runs `zig build run`, so we create a dependency link.
-    const run_cmd = b.addRunArtifact(pong_with_c_bindings);
-    run_step.dependOn(&run_cmd.step);
+    const run_pong_with_c_bindings_cmd = b.addRunArtifact(pong_with_c_bindings);
+    run_pong_with_c_bindings_step.dependOn(&run_pong_with_c_bindings_cmd.step);
 
     // By making the run step depend on the default step, it will be run from the
     // installation directory rather than directly from within the cache directory.
-    run_cmd.step.dependOn(b.getInstallStep());
+    run_pong_with_c_bindings_cmd.step.dependOn(b.getInstallStep());
 
     // This allows the user to pass arguments to the application in the build
     // command itself, like this: `zig build run -- arg1 arg2 etc`
     if (b.args) |args| {
-        run_cmd.addArgs(args);
+        run_pong_with_c_bindings_cmd.addArgs(args);
     }
 
     // Creates an executable that will run `test` blocks from the provided module.

src/examples/pong-with-c-bindings.zig

@@ -53,7 +53,7 @@ pub fn main() !u8 {
     libipc.ipc_context_timer (ctx, 1000);
 
     var should_continue : bool = true;
-    var event_count : u32 = 0;
+    // var event_count : u32 = 0;
 
     std.debug.print("Let's loop over events.\n", .{});
     while(should_continue) {
@@ -66,8 +66,8 @@ pub fn main() !u8 {
             return 1;
         }
 
-        event_count += 1;
-        std.debug.print("EVENT n°{d} type {d}\t", .{ event_count, event_type });
+        // event_count += 1;
+        // std.debug.print("EVENT n°{d} type {d}\t", .{ event_count, event_type });
 
         switch (event_type) {
             libipc.ERROR         =>  { std.debug.print("Error.", .{});                            return 1; },
@@ -84,7 +84,7 @@ pub fn main() !u8 {
                     return 1;
                 }
                 buffer[size] = 0;
-                std.debug.print("Response (size {d}): {s}.\n", .{ size, buffer });
+                std.debug.print("Response (size {d}): {s}.\n", .{ size, buffer[0..size] });
                 // We received the response, quitting.
                 should_continue = false;
             },

src/examples/pongd-with-c-bindings.zig

@@ -0,0 +1,100 @@
+// Example of a `pong` service using the C bindings.
+const std = @import("std");
+
+// Only bindings are available.
+const libipc = @cImport({
+    @cInclude("../../../libipc.h");
+});
+
+const SERVICE = "pong";
+const SERVICE_LEN = 4;
+const MAX_MSG_SIZE = 10000;
+
+pub fn main() !u8 {
+    var ctx        : *anyopaque       = undefined;
+    var ret        : c_int            = 0;
+    var servicefd  : c_int            = undefined;
+    var buffer     : [MAX_MSG_SIZE]u8 = undefined;
+    var size       : usize            = MAX_MSG_SIZE;
+    var event_type : u8               = undefined;
+    var index      : usize            = 0;
+    var originfd   : c_int            = undefined;
+
+    std.debug.print("Init context.\n", .{});
+    ret = libipc.ipc_context_init (@ptrCast(&ctx));
+
+    if (ret != 0) {
+        std.debug.print("Cannot init context.\n", .{});
+        return 1;
+    }
+
+    defer {
+        std.debug.print("Deinit context.\n", .{});
+        libipc.ipc_context_deinit (@ptrCast(&ctx));
+    }
+
+    std.debug.print ("Create the 'pong' service.\n", .{});
+    ret = libipc.ipc_service_init (ctx, &servicefd, SERVICE, SERVICE_LEN);
+
+    if (ret != 0) {
+        std.debug.print("Cannot create the service.\n", .{});
+        return 1;
+    }
+
+    std.debug.print ("Listening to the standard input (press enter to quit).\n", .{});
+    ret = libipc.ipc_add_external (ctx, 0);
+
+    if (ret != 0) {
+        std.debug.print ("Cannot listen to standard input.", .{});
+        return 1;
+    }
+
+    std.debug.print("Set the timer to two seconds.\n", .{});
+    libipc.ipc_context_timer (ctx, 2000);
+
+    var event_count : u32 = 0;
+
+    std.debug.print("Let's loop over events.\n", .{});
+    while(true) {
+        size = MAX_MSG_SIZE;
+        var newfd : c_int = undefined;
+        const pbuffer : [*c]u8 = &buffer;
+        ret = libipc.ipc_wait_event (ctx, &event_type, &index, &originfd, &newfd, pbuffer, &size);
+        if (ret != 0) {
+            std.debug.print("Error while waiting for an event.", .{});
+            return 1;
+        }
+
+        event_count += 1;
+
+        switch (event_type) {
+            libipc.ERROR         =>  { std.debug.print("Error.", .{});                            return 1; },
+            libipc.EXTERNAL      =>  { std.debug.print("Quitting.\n", .{});                       return 0; },
+            libipc.SWITCH_RX     =>  { std.debug.print("Switch RX (shouldn't happen).", .{});     return 1; },
+            libipc.SWITCH_TX     =>  { std.debug.print("Switch TX (shouldn't happen).", .{});     return 1; },
+            libipc.CONNECTION    =>  { std.debug.print("Connection (fd {d}).\n", .{newfd});                 },
+            libipc.DISCONNECTION =>  { std.debug.print("Disconnection (fd {d}).\n", .{originfd});           },
+            libipc.TIMER         =>  { std.debug.print("\rTIMER ({d}).\r", .{event_count});                 },
+            libipc.MESSAGE_TX    =>  { std.debug.print("A message has been sent.\n", .{});                  },
+            libipc.MESSAGE_RX    =>  {
+                if (size == 0) {
+                    std.debug.print("No message returned.\n", .{});
+                    return 1;
+                }
+                buffer[size] = 0;
+                std.debug.print("Message from {d} (size {d}): {s}.\n", .{ originfd, size, buffer[0..size] });
+
+                std.debug.print ("Schedule a message for {d}.\n", .{originfd});
+                ret = libipc.ipc_schedule (ctx, originfd, pbuffer, size);
+
+                if (ret != 0) {
+                    std.debug.print("Cannot schedule a message.\n", .{});
+                    return 1;
+                }
+            },
+            else =>                  { std.debug.print("Unknown IPC message type.\n", .{});       return 1; },
+        }
+    }
+
+    return 0;
+}