diff -r 000000000000 -r d2d88f14283e pre-inst/post.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/pre-inst/post.c	Wed Jul 15 11:54:06 2020 +0100
@@ -0,0 +1,198 @@
+/*
+ * Copyright (C) 2020  J. Ali Harlow <ali@juiblex.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <string.h>
+#include <glib.h>
+#include <expat.h>
+#include <razor.h>
+#include <plover/plover.h>
+#include "pre-inst/post.h"
+
+#define PLOVER_XML_NS "http://project.juiblex.co.uk/plover/ns/2009"
+
+enum post_state {
+    POST_STATE_BEGIN,
+    POST_STATE_ROOT,
+    POST_STATE_ARGUMENT,
+    POST_STATE_INSTALL_PREFIX,
+    POST_STATE_REPOSITORY,
+};
+
+struct post_context {
+    struct post *post;
+    enum post_state state;
+    int unknown_elements;
+    GPtrArray *args;
+    GString *str;
+};
+
+static void post_start_element(void *data,const char *name,const char **atts)
+{
+    struct post_context *ctx=data;
+    if (ctx->unknown_elements)
+	ctx->unknown_elements++;
+    else if (ctx->state==POST_STATE_BEGIN &&
+      !strcmp(name,PLOVER_XML_NS "\xFF" "post"))
+	ctx->state=POST_STATE_ROOT;
+    else if (ctx->state==POST_STATE_ROOT &&
+      !strcmp(name,PLOVER_XML_NS "\xFF" "command"))
+    {
+	ctx->state=POST_STATE_ARGUMENT;
+	if (ctx->args->len>0)
+	{
+	    ctx->str=g_ptr_array_index(ctx->args,0);
+	    g_string_truncate(ctx->str,0);
+	}
+	else
+	{
+	    ctx->str=g_string_new(NULL);
+	    g_ptr_array_add(ctx->args,ctx->str);
+	}
+    }
+    else if (ctx->state==POST_STATE_ROOT &&
+      !strcmp(name,PLOVER_XML_NS "\xFF" "argument"))
+    {
+	ctx->state=POST_STATE_ARGUMENT;
+	ctx->str=g_string_new(NULL);
+	if (ctx->args->len==0)
+	    g_ptr_array_add(ctx->args,NULL);
+	g_ptr_array_add(ctx->args,ctx->str);
+    }
+    else if (ctx->state==POST_STATE_ARGUMENT)
+    {
+	if (!strcmp(name,PLOVER_XML_NS "\xFF" "install-prefix"))
+	    ctx->state=POST_STATE_INSTALL_PREFIX;
+	else if (!strcmp(name,PLOVER_XML_NS "\xFF" "repository"))
+	    ctx->state=POST_STATE_REPOSITORY;
+	else
+	    ctx->unknown_elements++;
+    }
+    else
+	ctx->unknown_elements++;
+}
+
+static void post_end_element(void *data,const char *name)
+{
+    struct post_context *ctx=data;
+    if (ctx->unknown_elements)
+	ctx->unknown_elements--;
+    else
+	switch (ctx->state)
+	{
+	    case POST_STATE_ROOT:
+		ctx->state=POST_STATE_BEGIN;
+		break;
+	    case POST_STATE_ARGUMENT:
+		ctx->state=POST_STATE_ROOT;
+		break;
+	    case POST_STATE_INSTALL_PREFIX:
+		if (ctx->post->install_prefix)
+		    g_string_append(ctx->str,ctx->post->install_prefix);
+		ctx->state=POST_STATE_ARGUMENT;
+		break;
+	    case POST_STATE_REPOSITORY:
+		if (ctx->post->repository)
+		    g_string_append(ctx->str,ctx->post->repository);
+		ctx->state=POST_STATE_ARGUMENT;
+		break;
+	}
+}
+
+static void post_character_data(void *data,const XML_Char *s,int len)
+{
+    struct post_context *ctx=data;
+    switch (ctx->state)
+    {
+	case POST_STATE_ARGUMENT:
+	    g_string_append_len(ctx->str,s,len);
+	    break;
+    }
+}
+
+struct post *pre_install_post_new(const char *repository,
+  const char *install_prefix)
+{
+    struct post *post;
+    post=g_new0(struct post,1);
+    post->repository=g_strdup(repository);
+    post->install_prefix=g_strdup(install_prefix);
+    return post;
+}
+
+void pre_install_post_free(struct post *post)
+{
+    g_free(post->repository);
+    g_free(post->install_prefix);
+    g_free(post);
+}
+
+gboolean pre_install_post_load_uri(struct post *post,const char *uri,
+  GError **error)
+{
+    int i;
+    gboolean retval;
+    struct post_context ctx={0,};
+    struct razor_error *tmp_error=NULL;
+    size_t length;
+    void *contents;
+    XML_Parser parser;
+    contents=razor_uri_get_contents(uri,&length,FALSE,&tmp_error);
+    if (!contents)
+    {
+	plover_propagate_razor_error(error,tmp_error);
+	return FALSE;
+    }
+    parser=XML_ParserCreateNS(NULL,'\xFF');
+    ctx.post=post;
+    ctx.state=POST_STATE_BEGIN;
+    ctx.args=g_ptr_array_new();
+    XML_SetUserData(parser,&ctx);
+    XML_SetElementHandler(parser,post_start_element,post_end_element);
+    XML_SetCharacterDataHandler(parser,post_character_data);
+    retval=XML_Parse(parser,contents,length,TRUE)!=XML_STATUS_ERROR;
+    if (!retval)
+	g_set_error(error,PLOVER_GENERAL_ERROR,PLOVER_GENERAL_ERROR_FAILED,
+	  "%s on line %d of '%s'\n",
+	  XML_ErrorString(XML_GetErrorCode(parser)),
+	  XML_GetCurrentLineNumber(parser),uri);
+    XML_ParserFree(parser);
+    razor_uri_free_contents(contents,length);
+    if (retval)
+    {
+	if (ctx.args->len>0 && !g_ptr_array_index(ctx.args,0))
+	    g_warning("post: ignoring arguments because no command specified");
+	if (post->argv)
+	    g_strfreev(post->argv);
+	if (ctx.args->len>0 && g_ptr_array_index(ctx.args,0))
+	{
+	    post->argc=ctx.args->len;
+	    post->argv=g_new(gchar *,post->argc+1);
+	    for(i=0;i<post->argc;i++)
+		post->argv[i]=
+		  g_string_free(g_ptr_array_index(ctx.args,i),FALSE);
+	    post->argv[i]=NULL;
+	}
+	else
+	{
+	    post->argc=0;
+	    post->argv=g_new0(gchar *,1);
+	}
+	g_ptr_array_free(ctx.args,FALSE);
+    }
+    return retval;
+}