Implement configuration file parsing

src/config.c

@@ -0,0 +1,114 @@
+/*
+ * vim:ts=8:expandtab
+ *
+ * i3 - an improved dynamic tiling window manager
+ *
+ * © 2009 Michael Stapelberg and contributors
+ *
+ * See file LICENSE for license information.
+ *
+ */
+#include <stdio.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <stdlib.h>
+
+#include "i3.h"
+#include "util.h"
+#include "config.h"
+
+Config config;
+
+/*
+ * Reads the configuration from the given file
+ *
+ */
+void load_configuration(const char *configfile) {
+#define OPTION_STRING(name) \
+        if (strcasecmp(key, #name) == 0) { \
+                config.name = sstrdup(value); \
+                continue; \
+        }
+
+#define REQUIRED_OPTION(name) \
+        if (config.name == NULL) \
+                die("You did not specify required configuration option " #name "\n");
+
+        /* Clear the old config or initialize the data structure */
+        memset(&config, 0, sizeof(config));
+
+        /* check if the file exists */
+        struct stat buf;
+        if (stat(configfile, &buf) < 0)
+                return;
+
+        FILE *handle = fopen(configfile, "r");
+        if (handle == NULL)
+                die("Could not open configfile\n");
+        char key[512], value[512], buffer[1026];
+
+        while (!feof(handle)) {
+                if (fgets(buffer, 1024, handle) == NULL) {
+                        /* fgets returns NULL on EOF and on error, so see which one it is. */
+                        if (feof(handle))
+                                break;
+                        die("Could not read configuration file\n");
+                }
+
+                /* sscanf implicitly strips whitespace. Also, we skip comments and empty lines. */
+                if (sscanf(buffer, "%s %[^\n]", key, value) < 1 ||
+                    key[0] == '#' || strlen(key) < 3)
+                        continue;
+
+                OPTION_STRING(terminal);
+                OPTION_STRING(font);
+
+                if (strcasecmp(key, "bind") == 0) {
+                        #define CHECK_MODIFIER(name) \
+                                if (strncasecmp(walk, #name, strlen(#name)) == 0) { \
+                                        modifiers |= BIND_##name; \
+                                        walk += strlen(#name) + 1; \
+                                        continue; \
+                                }
+                        char *walk = value, *rest;
+                        uint32_t modifiers = 0;
+
+                        while (*walk != '\0') {
+                                /* Need to check for Mod1-5, Ctrl, Shift, Mode_switch */
+                                CHECK_MODIFIER(SHIFT);
+                                CHECK_MODIFIER(CONTROL);
+                                CHECK_MODIFIER(MODE_SWITCH);
+                                CHECK_MODIFIER(MOD1);
+                                CHECK_MODIFIER(MOD2);
+                                CHECK_MODIFIER(MOD3);
+                                CHECK_MODIFIER(MOD4);
+                                CHECK_MODIFIER(MOD5);
+
+                                /* No modifier found? Then we’re done with this step */
+                                break;
+                        }
+
+                        /* Now check for the keycode */
+                        int keycode = strtol(walk, &rest, 10);
+                        if (!rest || *rest != ' ')
+                                die("Invalid binding\n");
+                        rest++;
+                        printf("keycode = %d, modifiers = %d, command = *%s*\n", keycode, modifiers, rest);
+                        Binding *new = smalloc(sizeof(Binding));
+                        new->keycode = keycode;
+                        new->mods = modifiers;
+                        new->command = sstrdup(rest);
+                        TAILQ_INSERT_TAIL(&bindings, new, bindings);
+                        continue;
+                }
+
+                fprintf(stderr, "Unknown configfile option: %s\n", key);
+                exit(1);
+        }
+        fclose(handle);
+
+        REQUIRED_OPTION(terminal);
+        REQUIRED_OPTION(font);
+
+        return;
+}