--- /dev/null
+#undef I3__FILE__
+#define I3__FILE__ "config_parser.c"
+/*
+ * vim:ts=4:sw=4:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ * © 2009-2012 Michael Stapelberg and contributors (see also: LICENSE)
+ *
+ * config_parser.c: hand-written parser to parse configuration directives.
+ *
+ * See also src/commands_parser.c for rationale on why we use a custom parser.
+ *
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "all.h"
+
+// Macros to make the YAJL API a bit easier to use.
+#define y(x, ...) yajl_gen_ ## x (command_output.json_gen, ##__VA_ARGS__)
+#define ystr(str) yajl_gen_string(command_output.json_gen, (unsigned char*)str, strlen(str))
+
+/*******************************************************************************
+ * The data structures used for parsing. Essentially the current state and a
+ * list of tokens for that state.
+ *
+ * The GENERATED_* files are generated by generate-commands-parser.pl with the
+ * input parser-specs/configs.spec.
+ ******************************************************************************/
+
+#include "GENERATED_config_enums.h"
+
+typedef struct token {
+ char *name;
+ char *identifier;
+ /* This might be __CALL */
+ cmdp_state next_state;
+ union {
+ uint16_t call_identifier;
+ } extra;
+} cmdp_token;
+
+typedef struct tokenptr {
+ cmdp_token *array;
+ int n;
+} cmdp_token_ptr;
+
+#include "GENERATED_config_tokens.h"
+
+/*******************************************************************************
+ * The (small) stack where identified literals are stored during the parsing
+ * of a single command (like $workspace).
+ ******************************************************************************/
+
+struct stack_entry {
+ /* Just a pointer, not dynamically allocated. */
+ const char *identifier;
+ char *str;
+};
+
+/* 10 entries should be enough for everybody. */
+static struct stack_entry stack[10];
+
+/*
+ * Pushes a string (identified by 'identifier') on the stack. We simply use a
+ * single array, since the number of entries we have to store is very small.
+ *
+ */
+static void push_string(const char *identifier, char *str) {
+ for (int c = 0; c < 10; c++) {
+ if (stack[c].identifier != NULL &&
+ strcmp(stack[c].identifier, identifier) != 0)
+ continue;
+ if (stack[c].identifier == NULL) {
+ /* Found a free slot, let’s store it here. */
+ stack[c].identifier = identifier;
+ stack[c].str = str;
+ } else {
+ /* Append the value. */
+ sasprintf(&(stack[c].str), "%s,%s", stack[c].str, str);
+ }
+ return;
+ }
+
+ /* When we arrive here, the stack is full. This should not happen and
+ * means there’s either a bug in this parser or the specification
+ * contains a command with more than 10 identified tokens. */
+ fprintf(stderr, "BUG: commands_parser stack full. This means either a bug "
+ "in the code, or a new command which contains more than "
+ "10 identified tokens.\n");
+ exit(1);
+}
+
+// XXX: ideally, this would be const char. need to check if that works with all
+// called functions.
+static char *get_string(const char *identifier) {
+ for (int c = 0; c < 10; c++) {
+ if (stack[c].identifier == NULL)
+ break;
+ if (strcmp(identifier, stack[c].identifier) == 0)
+ return stack[c].str;
+ }
+ return NULL;
+}
+
+static void clear_stack(void) {
+ for (int c = 0; c < 10; c++) {
+ if (stack[c].str != NULL)
+ free(stack[c].str);
+ stack[c].identifier = NULL;
+ stack[c].str = NULL;
+ }
+}
+
+// TODO: remove this if it turns out we don’t need it for testing.
+#if 0
+/*******************************************************************************
+ * A dynamically growing linked list which holds the criteria for the current
+ * command.
+ ******************************************************************************/
+
+typedef struct criterion {
+ char *type;
+ char *value;
+
+ TAILQ_ENTRY(criterion) criteria;
+} criterion;
+
+static TAILQ_HEAD(criteria_head, criterion) criteria =
+ TAILQ_HEAD_INITIALIZER(criteria);
+
+/*
+ * Stores the given type/value in the list of criteria.
+ * Accepts a pointer as first argument, since it is 'call'ed by the parser.
+ *
+ */
+static void push_criterion(void *unused_criteria, const char *type,
+ const char *value) {
+ struct criterion *criterion = malloc(sizeof(struct criterion));
+ criterion->type = strdup(type);
+ criterion->value = strdup(value);
+ TAILQ_INSERT_TAIL(&criteria, criterion, criteria);
+}
+
+/*
+ * Clears the criteria linked list.
+ * Accepts a pointer as first argument, since it is 'call'ed by the parser.
+ *
+ */
+static void clear_criteria(void *unused_criteria) {
+ struct criterion *criterion;
+ while (!TAILQ_EMPTY(&criteria)) {
+ criterion = TAILQ_FIRST(&criteria);
+ free(criterion->type);
+ free(criterion->value);
+ TAILQ_REMOVE(&criteria, criterion, criteria);
+ free(criterion);
+ }
+}
+#endif
+
+/*******************************************************************************
+ * The parser itself.
+ ******************************************************************************/
+
+static cmdp_state state;
+#ifndef TEST_PARSER
+static Match current_match;
+#endif
+static struct CommandResult subcommand_output;
+static struct CommandResult command_output;
+
+#include "GENERATED_config_call.h"
+
+
+static void next_state(const cmdp_token *token) {
+ //printf("token = name %s identifier %s\n", token->name, token->identifier);
+ //printf("next_state = %d\n", token->next_state);
+ if (token->next_state == __CALL) {
+ subcommand_output.json_gen = command_output.json_gen;
+ subcommand_output.needs_tree_render = false;
+ GENERATED_call(token->extra.call_identifier, &subcommand_output);
+ /* If any subcommand requires a tree_render(), we need to make the
+ * whole parser result request a tree_render(). */
+ if (subcommand_output.needs_tree_render)
+ command_output.needs_tree_render = true;
+ clear_stack();
+ return;
+ }
+
+ state = token->next_state;
+ if (state == INITIAL) {
+ clear_stack();
+ }
+}
+
+struct CommandResult *parse_config(const char *input) {
+ DLOG("COMMAND: *%s*\n", input);
+ state = INITIAL;
+
+/* A YAJL JSON generator used for formatting replies. */
+#if YAJL_MAJOR >= 2
+ command_output.json_gen = yajl_gen_alloc(NULL);
+#else
+ command_output.json_gen = yajl_gen_alloc(NULL, NULL);
+#endif
+
+ y(array_open);
+ command_output.needs_tree_render = false;
+
+ const char *walk = input;
+ const size_t len = strlen(input);
+ int c;
+ const cmdp_token *token;
+ bool token_handled;
+
+ // TODO: make this testable
+#ifndef TEST_PARSER
+ cmd_criteria_init(¤t_match, &subcommand_output);
+#endif
+
+ /* The "<=" operator is intentional: We also handle the terminating 0-byte
+ * explicitly by looking for an 'end' token. */
+ while ((walk - input) <= len) {
+ /* skip whitespace and newlines before every token */
+ while ((*walk == ' ' || *walk == '\t' ||
+ *walk == '\r' || *walk == '\n') && *walk != '\0')
+ walk++;
+
+ //printf("remaining input: %s\n", walk);
+
+ cmdp_token_ptr *ptr = &(tokens[state]);
+ token_handled = false;
+ for (c = 0; c < ptr->n; c++) {
+ token = &(ptr->array[c]);
+
+ /* A literal. */
+ if (token->name[0] == '\'') {
+ if (strncasecmp(walk, token->name + 1, strlen(token->name) - 1) == 0) {
+ if (token->identifier != NULL)
+ push_string(token->identifier, sstrdup(token->name + 1));
+ walk += strlen(token->name) - 1;
+ next_state(token);
+ token_handled = true;
+ break;
+ }
+ continue;
+ }
+
+ if (strcmp(token->name, "string") == 0 ||
+ strcmp(token->name, "word") == 0) {
+ const char *beginning = walk;
+ /* Handle quoted strings (or words). */
+ if (*walk == '"') {
+ beginning++;
+ walk++;
+ while (*walk != '\0' && (*walk != '"' || *(walk-1) == '\\'))
+ walk++;
+ } else {
+ if (token->name[0] == 's') {
+ /* For a string (starting with 's'), the delimiters are
+ * comma (,) and semicolon (;) which introduce a new
+ * operation or command, respectively. Also, newlines
+ * end a command. */
+ while (*walk != ';' && *walk != ',' &&
+ *walk != '\0' && *walk != '\r' &&
+ *walk != '\n')
+ walk++;
+ } else {
+ /* For a word, the delimiters are white space (' ' or
+ * '\t'), closing square bracket (]), comma (,) and
+ * semicolon (;). */
+ while (*walk != ' ' && *walk != '\t' &&
+ *walk != ']' && *walk != ',' &&
+ *walk != ';' && *walk != '\r' &&
+ *walk != '\n' && *walk != '\0')
+ walk++;
+ }
+ }
+ if (walk != beginning) {
+ char *str = scalloc(walk-beginning + 1);
+ /* We copy manually to handle escaping of characters. */
+ int inpos, outpos;
+ for (inpos = 0, outpos = 0;
+ inpos < (walk-beginning);
+ inpos++, outpos++) {
+ /* We only handle escaped double quotes to not break
+ * backwards compatibility with people using \w in
+ * regular expressions etc. */
+ if (beginning[inpos] == '\\' && beginning[inpos+1] == '"')
+ inpos++;
+ str[outpos] = beginning[inpos];
+ }
+ if (token->identifier)
+ push_string(token->identifier, str);
+ /* If we are at the end of a quoted string, skip the ending
+ * double quote. */
+ if (*walk == '"')
+ walk++;
+ next_state(token);
+ token_handled = true;
+ break;
+ }
+ }
+
+ if (strcmp(token->name, "end") == 0) {
+ if (*walk == '\0' || *walk == ',' || *walk == ';') {
+ next_state(token);
+ token_handled = true;
+ /* To make sure we start with an appropriate matching
+ * datastructure for commands which do *not* specify any
+ * criteria, we re-initialize the criteria system after
+ * every command. */
+ // TODO: make this testable
+#ifndef TEST_PARSER
+ if (*walk == '\0' || *walk == ';')
+ cmd_criteria_init(¤t_match, &subcommand_output);
+#endif
+ walk++;
+ break;
+ }
+ }
+ }
+
+ if (!token_handled) {
+ /* Figure out how much memory we will need to fill in the names of
+ * all tokens afterwards. */
+ int tokenlen = 0;
+ for (c = 0; c < ptr->n; c++)
+ tokenlen += strlen(ptr->array[c].name) + strlen("'', ");
+
+ /* Build up a decent error message. We include the problem, the
+ * full input, and underline the position where the parser
+ * currently is. */
+ char *errormessage;
+ char *possible_tokens = smalloc(tokenlen + 1);
+ char *tokenwalk = possible_tokens;
+ for (c = 0; c < ptr->n; c++) {
+ token = &(ptr->array[c]);
+ if (token->name[0] == '\'') {
+ /* A literal is copied to the error message enclosed with
+ * single quotes. */
+ *tokenwalk++ = '\'';
+ strcpy(tokenwalk, token->name + 1);
+ tokenwalk += strlen(token->name + 1);
+ *tokenwalk++ = '\'';
+ } else {
+ /* Any other token is copied to the error message enclosed
+ * with angle brackets. */
+ *tokenwalk++ = '<';
+ strcpy(tokenwalk, token->name);
+ tokenwalk += strlen(token->name);
+ *tokenwalk++ = '>';
+ }
+ if (c < (ptr->n - 1)) {
+ *tokenwalk++ = ',';
+ *tokenwalk++ = ' ';
+ }
+ }
+ *tokenwalk = '\0';
+ sasprintf(&errormessage, "Expected one of these tokens: %s",
+ possible_tokens);
+ free(possible_tokens);
+
+ /* Contains the same amount of characters as 'input' has, but with
+ * the unparseable part highlighted using ^ characters. */
+ char *position = smalloc(len + 1);
+ for (const char *copywalk = input; *copywalk != '\0'; copywalk++)
+ position[(copywalk - input)] = (copywalk >= walk ? '^' : ' ');
+ position[len] = '\0';
+
+ ELOG("%s\n", errormessage);
+ ELOG("Your command: %s\n", input);
+ ELOG(" %s\n", position);
+
+ /* Format this error message as a JSON reply. */
+ y(map_open);
+ ystr("success");
+ y(bool, false);
+ /* We set parse_error to true to distinguish this from other
+ * errors. i3-nagbar is spawned upon keypresses only for parser
+ * errors. */
+ ystr("parse_error");
+ y(bool, true);
+ ystr("error");
+ ystr(errormessage);
+ ystr("input");
+ ystr(input);
+ ystr("errorposition");
+ ystr(position);
+ y(map_close);
+
+ free(position);
+ free(errormessage);
+ clear_stack();
+ break;
+ }
+ }
+
+ y(array_close);
+
+ return &command_output;
+}
+
+/*******************************************************************************
+ * Code for building the stand-alone binary test.commands_parser which is used
+ * by t/187-commands-parser.t.
+ ******************************************************************************/
+
+#ifdef TEST_PARSER
+
+/*
+ * Logs the given message to stdout while prefixing the current time to it,
+ * but only if debug logging was activated.
+ * This is to be called by DLOG() which includes filename/linenumber
+ *
+ */
+void debuglog(char *fmt, ...) {
+ va_list args;
+
+ va_start(args, fmt);
+ fprintf(stdout, "# ");
+ vfprintf(stdout, fmt, args);
+ va_end(args);
+}
+
+void errorlog(char *fmt, ...) {
+ va_list args;
+
+ va_start(args, fmt);
+ vfprintf(stderr, fmt, args);
+ va_end(args);
+}
+
+int main(int argc, char *argv[]) {
+ if (argc < 2) {
+ fprintf(stderr, "Syntax: %s <command>\n", argv[0]);
+ return 1;
+ }
+ parse_config(argv[1]);
+}
+#endif
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