Use NULL instead of 0 for pointer arguments

diff --git a/gatmux/gsm0710.c b/gatmux/gsm0710.c
index 279a9a2..59bd613 100644 (file)
--- a/gatmux/gsm0710.c
+++ b/gatmux/gsm0710.c
@@ -269,7 +269,7 @@ int gsm0710_startup(struct gsm0710_context *ctx, int send_cmux)
        }
 
        /* Open the control channel */
-       gsm0710_write_frame(ctx, 0, GSM0710_OPEN_CHANNEL, 0, 0);
+       gsm0710_write_frame(ctx, 0, GSM0710_OPEN_CHANNEL, NULL, 0);
 
        /* Open previously-used channels if this is a reinit.
           Send "ERROR" on re-opened channels, to cause higher
@@ -277,7 +277,7 @@ int gsm0710_startup(struct gsm0710_context *ctx, int send_cmux)
        for (channel = 1; channel <= GSM0710_MAX_CHANNELS; ++channel) {
                if (is_channel_used(ctx, channel)) {
                        gsm0710_write_frame(ctx, channel,
-                                               GSM0710_OPEN_CHANNEL, 0, 0);
+                                               GSM0710_OPEN_CHANNEL, NULL, 0);
                        if (ctx->deliver_data)
                                ctx->deliver_data(ctx, channel,
                                                        "\r\nERROR\r\n", 9);
@@ -296,7 +296,7 @@ void gsm0710_shutdown(struct gsm0710_context *ctx)
                for (channel = 1; channel <= GSM0710_MAX_CHANNELS; ++channel) {
                        if (is_channel_used(ctx, channel)) {
                                gsm0710_write_frame(ctx, channel,
-                                               GSM0710_CLOSE_CHANNEL, 0, 0);
+                                               GSM0710_CLOSE_CHANNEL, NULL, 0);
                        }
                }
                gsm0710_write_frame(ctx, 0, GSM0710_DATA, terminate, 2);
@@ -313,7 +313,8 @@ int gsm0710_open_channel(struct gsm0710_context *ctx, int channel)
                return 1;       /* Channel is already open */
        mark_channel_used(ctx, channel);
        if (!ctx->server)
-               gsm0710_write_frame(ctx, channel, GSM0710_OPEN_CHANNEL, 0, 0);
+               gsm0710_write_frame(ctx, channel,
+                                       GSM0710_OPEN_CHANNEL, NULL, 0);
        return 1;
 }
 
@@ -326,7 +327,8 @@ void gsm0710_close_channel(struct gsm0710_context *ctx, int channel)
                return;         /* Channel is already closed */
        mark_channel_unused(ctx, channel);
        if (!ctx->server)
-               gsm0710_write_frame(ctx, channel, GSM0710_CLOSE_CHANNEL, 0, 0);
+               gsm0710_write_frame(ctx, channel,
+                                       GSM0710_CLOSE_CHANNEL, NULL, 0);
 }
 
 /* Determine if a specific channel is open */