blogc-make: implemented automatic reloader for runserver rule

this is not the best implementation possible, but it works for most use
cases

1 files changed, 107 insertions, 3 deletions

diff --git a/src/blogc-make/ctx.c b/src/blogc-make/ctx.c
index 39f1bf4..2dd4f97 100644
--- a/src/blogc-make/ctx.c
+++ b/src/blogc-make/ctx.c
@@ -50,6 +50,49 @@ bm_filectx_new(bm_ctx_t *ctx, const char *filename)
 }
 
 
+bool
+bm_filectx_changed(bm_filectx_t *ctx, struct timespec *ts)
+{
+    if (ctx == NULL)
+        return false;
+
+    struct stat buf;
+
+    if (0 == stat(ctx->path, &buf)) {
+        if (buf.st_mtim.tv_sec == ctx->timestamp.tv_sec) {
+            if (buf.st_mtim.tv_nsec > ctx->timestamp.tv_nsec) {
+                if (ts != NULL)
+                    *ts = buf.st_mtim;
+                return true;
+            }
+        }
+        else if (buf.st_mtim.tv_sec > ctx->timestamp.tv_sec) {
+            if (ts != NULL)
+                *ts = buf.st_mtim;
+            return true;
+        }
+    }
+
+    return false;
+}
+
+
+void
+bm_filectx_reload(bm_filectx_t *ctx)
+{
+    if (ctx == NULL)
+        return;
+
+    struct timespec ts;
+
+    if (!bm_filectx_changed(ctx, &ts))
+        return;
+
+    ctx->timestamp = ts;
+    ctx->readable = true;
+}
+
+
 void
 bm_filectx_free(bm_filectx_t *fctx)
 {
@@ -62,7 +105,7 @@ bm_filectx_free(bm_filectx_t *fctx)
 
 
 bm_ctx_t*
-bm_ctx_new(const char *settings_file, bc_error_t **err)
+bm_ctx_new(bm_ctx_t *base, const char *settings_file, bc_error_t **err)
 {
     if (settings_file == NULL || err == NULL || *err != NULL)
         return NULL;
@@ -92,7 +135,14 @@ bm_ctx_new(const char *settings_file, bc_error_t **err)
         return NULL;
     }
 
-    bm_ctx_t *rv = bc_malloc(sizeof(bm_ctx_t));
+    bm_ctx_t *rv = NULL;
+    if (base == NULL) {
+        rv = bc_malloc(sizeof(bm_ctx_t));
+    }
+    else {
+        bm_ctx_free_internal(base);
+        rv = base;
+    }
     rv->settings = settings;
 
     char *real_filename = realpath(settings_file, NULL);
@@ -108,6 +158,8 @@ bm_ctx_new(const char *settings_file, bc_error_t **err)
         rv->output_dir = bc_strdup_printf("%s/%s", rv->root_dir, output_dir);
     }
 
+    // can't return null and set error after this!
+
     const char *template_dir = bc_trie_lookup(settings->settings,
         "template_dir");
 
@@ -158,25 +210,77 @@ bm_ctx_new(const char *settings_file, bc_error_t **err)
 
 
 void
-bm_ctx_free(bm_ctx_t *ctx)
+bm_ctx_reload(bm_ctx_t *ctx)
+{
+    if (ctx == NULL || ctx->settings_fctx == NULL)
+        return;
+
+    if (bm_filectx_changed(ctx->settings_fctx, NULL)) {
+        // reload everything! we could just reload settings_fctx, as this
+        // would force rebuilding everything, but we need to know new/deleted
+        // files
+
+        // needs to dup path, because it may be freed when reloading.
+        char *tmp = bc_strdup(ctx->settings_fctx->path);
+        bc_error_t *err = NULL;
+        ctx = bm_ctx_new(ctx, tmp, &err);
+        free(tmp);
+        if (err != NULL) {  // failed to reload, keep old ctx
+            bc_error_print(err, "blogc-make");
+            bc_error_free(err);
+        }
+        return;
+    }
+
+    bm_filectx_reload(ctx->main_template_fctx);
+    bm_filectx_reload(ctx->atom_template_fctx);
+
+    for (bc_slist_t *tmp = ctx->posts_fctx; tmp != NULL; tmp = tmp->next)
+        bm_filectx_reload((bm_filectx_t*) tmp->data);
+
+    for (bc_slist_t *tmp = ctx->pages_fctx; tmp != NULL; tmp = tmp->next)
+        bm_filectx_reload((bm_filectx_t*) tmp->data);
+
+    for (bc_slist_t *tmp = ctx->copy_files_fctx; tmp != NULL; tmp = tmp->next)
+        bm_filectx_reload((bm_filectx_t*) tmp->data);
+}
+
+
+void
+bm_ctx_free_internal(bm_ctx_t *ctx)
 {
     if (ctx == NULL)
         return;
 
     bm_settings_free(ctx->settings);
+    ctx->settings = NULL;
 
     free(ctx->root_dir);
+    ctx->root_dir = NULL;
     free(ctx->output_dir);
+    ctx->output_dir = NULL;
 
     bm_atom_destroy(ctx->atom_template_fctx->path);
 
     bm_filectx_free(ctx->main_template_fctx);
+    ctx->main_template_fctx = NULL;
     bm_filectx_free(ctx->atom_template_fctx);
+    ctx->atom_template_fctx = NULL;
     bm_filectx_free(ctx->settings_fctx);
+    ctx->settings_fctx = NULL;
 
     bc_slist_free_full(ctx->posts_fctx, (bc_free_func_t) bm_filectx_free);
+    ctx->posts_fctx = NULL;
     bc_slist_free_full(ctx->pages_fctx, (bc_free_func_t) bm_filectx_free);
+    ctx->pages_fctx = NULL;
     bc_slist_free_full(ctx->copy_files_fctx, (bc_free_func_t) bm_filectx_free);
+    ctx->copy_files_fctx = NULL;
+}
+
 
+void
+bm_ctx_free(bm_ctx_t *ctx)
+{
+    bm_ctx_free_internal(ctx);
     free(ctx);
 }