Initial revision

1 files changed, 444 insertions, 0 deletions

diff --git a/zwgc/exec.c b/zwgc/exec.c
new file mode 100644
index 0000000..e7ff111
--- /dev/null
+++ b/zwgc/exec.c
@@ -0,0 +1,444 @@
+/****************************************************************************/
+/*                                                                          */
+/*               Module containing code to execute a program:               */
+/*                                                                          */
+/****************************************************************************/
+
+#include <zephyr/zephyr.h>
+#include "new_memory.h"
+#include "exec.h"
+#include "eval.h"
+#include "node.h"
+#include "buffer.h"
+#include "port.h"
+#include "variables.h"
+#include "notice.h"
+
+/****************************************************************************/
+/*                                                                          */
+/*                           Utility subroutines:                          */
+/*                                                                          */
+/****************************************************************************/
+
+static string eval_exprlist_to_string(exprlist)
+     Node *exprlist;
+{
+    string result = string_Copy("");
+    string temp;
+    int first_time = 1;
+    
+    for (; exprlist; exprlist=exprlist->next) {
+	if (!first_time)
+	  result = string_Concat2(result, " ");
+	else
+	  first_time = 0;
+	
+	temp = eval_expr(exprlist);
+	result = string_Concat2(result, temp);
+	free(temp);
+    }
+    
+    return(result);
+}
+
+static char **eval_exprlist_to_args(exprlist)
+     Node *exprlist;
+{
+    char **result = (char **)malloc(sizeof(char *));
+    int argc = 0;
+
+    for (; exprlist; exprlist=exprlist->next) {
+	result[argc] = eval_expr(exprlist);
+	argc++;
+	result = (char **)realloc(result, (argc+1)*sizeof(char *));
+    }
+    
+    result[argc] = NULL;
+    return(result);
+}
+
+static void free_args(args)
+     char **args;
+{
+    char **p;
+
+    for (p=args; *p; p++) {
+      free(*p);
+  }
+	
+    free(args);
+}
+
+/****************************************************************************/
+/*                                                                          */
+/*          Subroutines to handle each particular statement type:           */
+/*                                                                          */
+/****************************************************************************/
+
+#define  NOBREAK   0
+#define  BREAK     1
+#define  EXIT      2
+
+/*ARGSUSED*/
+static int exec_noop(node)
+     Node *node;
+{
+    return(NOBREAK);
+}
+
+/*ARGSUSED*/
+static int exec_break(node)
+     Node *node;
+{
+    return(BREAK);
+}
+
+/*ARGSUSED*/
+static int exec_exit(node)
+     Node *node;
+{
+    return(EXIT);
+}
+
+static int exec_set(node)
+     Node *node;
+{
+    var_set_variable_then_free_value(node->d.nodes.first->d.string_constant,
+				     eval_expr(node->d.nodes.second));
+
+    return(NOBREAK);
+}
+
+static int exec_execport(node)
+     Node *node;
+{
+    string name = eval_expr(node->d.nodes.first);
+    char **argv = eval_exprlist_to_args(node->d.nodes.second);
+
+    create_subprocess_port(name, argv);
+
+    free(name);
+    free_args(argv);
+    return(NOBREAK);
+}
+
+static int exec_appendport(node)
+     Node *node;
+{
+    string name, filename;
+
+    name = eval_expr(node->d.nodes.first);
+    filename = eval_expr(node->d.nodes.second);
+
+    create_file_append_port(name, filename);
+
+    free(name);
+    free(filename);
+    return(NOBREAK);
+}
+
+static int exec_inputport(node)
+     Node *node;
+{
+    string name, filename;
+
+    name = eval_expr(node->d.nodes.first);
+    filename = eval_expr(node->d.nodes.second);
+
+    create_file_input_port(name, filename);
+
+    free(name);
+    free(filename);
+    return(NOBREAK);
+}
+
+static int exec_outputport(node)
+     Node *node;
+{
+    string name, filename;
+
+    name = eval_expr(node->d.nodes.first);
+    filename = eval_expr(node->d.nodes.second);
+
+    create_file_output_port(name, filename);
+
+    free(name);
+    free(filename);
+    return(NOBREAK);
+}
+
+static int exec_closeinput(node)
+     Node *node;
+{
+    string name;
+
+    name = eval_expr(node->d.nodes.first);
+    close_port_input(name);
+
+    free(name);
+    return(NOBREAK);
+}
+
+static int exec_closeoutput(node)
+     Node *node;
+{
+    string name;
+
+    name = eval_expr(node->d.nodes.first);
+    close_port_output(name);
+
+    free(name);
+    return(NOBREAK);
+}
+
+static int exec_closeport(node)
+     Node *node;
+{
+    string name;
+
+    name = eval_expr(node->d.nodes.first);
+    close_port_input(name);
+    close_port_output(name);
+
+    free(name);
+    return(NOBREAK);
+}
+
+static int exec_put(node)
+     Node *node;
+{
+    string name, temp;
+
+    if (node->d.nodes.second)
+      temp = eval_exprlist_to_string(node->d.nodes.second);
+    else
+      temp = string_Copy(buffer_to_string());
+
+    if (node->d.nodes.first) {
+	name = eval_expr(node->d.nodes.first);
+
+	write_on_port(name, temp, strlen(temp));
+	free(name);
+    } else
+      write_on_port(var_get_variable("output_driver"), temp, strlen(temp));
+
+    free(temp);
+    return(NOBREAK);
+}
+
+static int exec_print(node)
+     Node *node;
+{
+    string temp;
+
+    temp = eval_exprlist_to_string(node->d.nodes.first);
+    append_buffer(temp);
+    free(temp);
+    
+    return(NOBREAK);
+}
+
+/*ARGSUSED*/
+static int exec_clearbuf(node)
+     Node *node;
+{
+    clear_buffer();
+
+    return(NOBREAK);
+}
+
+static int exec_case(node)
+     Node *node;
+{
+    string constant,temp;
+    Node *match, *cond;
+    int equal_p;
+
+    constant = string_Downcase(eval_expr(node->d.nodes.first));
+   
+    for (match=node->d.nodes.second; match; match=match->next) {
+	cond = match->d.nodes.first;
+	if (!cond) {  /* default case */
+	    free(constant);
+	    return(exec_subtree(match->d.nodes.second));
+	}
+	for (; cond; cond=cond->next) {
+	    temp = string_Downcase(eval_expr(cond));
+	    equal_p = string_Eq(constant, temp);
+	    free(temp);
+	    if (equal_p) {
+		free(constant);
+		return(exec_subtree(match->d.nodes.second));
+	    }
+	}
+    }
+
+    free(constant);
+    return(NOBREAK);
+}
+
+static int exec_while(node)
+     Node *node;
+{
+    int continue_code = NOBREAK;
+
+    while (eval_bool_expr(node->d.nodes.first)) {
+	continue_code = exec_subtree(node->d.nodes.second);
+	if (continue_code != NOBREAK)
+	  break;
+    }
+
+    if (continue_code == BREAK)
+      continue_code = NOBREAK;
+
+    return(continue_code);
+}
+
+static int exec_if(node)
+     Node *node;
+{
+    Node *conds;
+
+    for (conds=node->d.nodes.first; conds; conds=conds->next)
+      if (eval_bool_expr(conds->d.nodes.first))
+	return(exec_subtree(conds->d.nodes.second));
+
+    return(NOBREAK);
+}
+
+static int exec_exec(node)
+     Node *node;
+{
+    int pid;
+    char **argv = eval_exprlist_to_args(node->d.nodes.first);
+
+    pid = fork();
+    if (pid == -1) {
+	fprintf(stderr, "zwgc: error while attempting to fork: ");
+	perror("");
+    } else if (pid == 0) { /* in child */
+	execvp(argv[0], argv);
+	fprintf(stderr,"zwgc: unable to exec %s: ", argv[0]);
+	perror("");
+	_exit(errno);
+    }
+    
+    free_args(argv);
+    return(NOBREAK);
+}
+
+/* <<<>>> */
+extern int exec_fields();
+
+static struct _Opstuff {
+    int (*exec)();
+} opstuff[] = {
+    { exec_noop },                         /* string_constant */
+    { exec_noop },                         /* varref */
+    { exec_noop },                         /* varname */
+    { exec_noop },                         /* not */
+    { exec_noop },                         /* plus */
+    { exec_noop },                         /* and */
+    { exec_noop },                         /* or */
+    { exec_noop },                         /* eq */
+    { exec_noop },                         /* neq */
+    { exec_noop },                         /* regeq */
+    { exec_noop },                         /* regneq */
+    { exec_noop },                         /* buffer */
+    { exec_noop },                         /* substitute */
+    { exec_noop },                         /* protect */
+    { exec_noop },                         /* verbatim */
+    { exec_noop },                         /* getenv */
+    { exec_noop },                         /* upcase */
+    { exec_noop },                         /* downcase */
+    { exec_noop },                         /* zvar */
+    { exec_noop },                         /* get */
+    { exec_noop },                         /* lany */
+    { exec_noop },                         /* rany */
+    { exec_noop },                         /* lbreak */
+    { exec_noop },                         /* rbreak */
+    { exec_noop },                         /* lspan */
+    { exec_noop },                         /* rspan */
+
+    { exec_noop },                          /* noop statement */
+    { exec_set },
+    { exec_fields },
+
+    { exec_print },
+    { exec_clearbuf },
+
+    { exec_appendport },
+    { exec_execport },
+    { exec_inputport },
+    { exec_outputport },
+    { exec_put },
+    { exec_closeinput },
+    { exec_closeoutput },
+    { exec_closeport },
+
+    { exec_exec },
+
+    { exec_if },
+    { exec_case },
+    { exec_while },
+    { exec_break },
+    { exec_exit },
+
+    { exec_noop },                           /* if */
+    { exec_noop },                           /* elseif */
+    { exec_noop },                           /* else */
+    { exec_noop },                           /* matchlist */
+    { exec_noop },                           /* default */
+};
+
+static int exec_subtree(node)
+     Node *node;
+{
+    int retval = NOBREAK;
+    
+    for (; node; node=node->next) {
+	retval = (opstuff[node->opcode].exec)(node);
+	if (retval != NOBREAK)
+	  return(retval);
+    }
+
+    return(NOBREAK);
+}
+
+/***************************************************************************/
+
+static char *notice_fields;
+static notice_fields_length = 0;
+static number_of_fields = 0;
+
+static int exec_fields(node)
+     Node *node;
+{
+    for (node=node->d.nodes.first; node; node=node->next) {
+	var_set_variable_then_free_value(node->d.string_constant,
+				 get_next_field(&notice_fields,
+						&notice_fields_length));
+	if (number_of_fields)
+	  number_of_fields--;
+    }
+    
+    var_set_variable_to_number("number_of_fields", number_of_fields);
+
+    return(NOBREAK);
+}
+
+void exec_process_packet(program, notice)
+     Node *program;
+     ZNotice_t *notice;
+{
+    notice_fields = notice->z_message;
+    notice_fields_length = notice->z_message_len;
+
+    var_set_number_variables_to_fields(notice_fields, notice_fields_length);
+
+    number_of_fields = count_nulls(notice_fields, notice_fields_length);
+    var_set_variable_to_number("number_of_fields", number_of_fields);
+
+    clear_buffer();
+    (void)exec_subtree(program);
+}