--- /dev/null
+/*
+ * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#include <sys/stat.h>
+#include <regex.h>
+
+#include <libubox/avl-cmp.h>
+
+#include "json_script.h"
+
+struct json_call {
+ struct json_script_ctx *ctx;
+ struct blob_attr *vars;
+ unsigned int seq;
+};
+
+struct json_handler {
+ const char *name;
+ int (*cb)(struct json_call *call, struct blob_attr *cur);
+};
+
+static int json_process_expr(struct json_call *call, struct blob_attr *cur);
+static int json_process_cmd(struct json_call *call, struct blob_attr *cur);
+
+struct json_script_file *
+json_script_file_from_blobmsg(const char *name, void *data, int len)
+{
+ struct json_script_file *f;
+ char *new_name;
+ int name_len = 0;
+
+ if (name)
+ name_len = strlen(name) + 1;
+
+ f = calloc_a(sizeof(*f) + len, &new_name, name_len);
+ memcpy(f->data, data, len);
+ if (name)
+ f->avl.key = strcpy(new_name, name);
+
+ return f;
+}
+
+static struct json_script_file *
+json_script_get_file(struct json_script_ctx *ctx, const char *filename)
+{
+ struct json_script_file *f;
+
+ f = avl_find_element(&ctx->files, filename, f, avl);
+ if (f)
+ return f;
+
+ f = ctx->handle_file(ctx, filename);
+ if (!f)
+ return NULL;
+
+ avl_insert(&ctx->files, &f->avl);
+ return f;
+}
+
+static void __json_script_run(struct json_call *call, struct json_script_file *file,
+ struct blob_attr *context)
+{
+ struct json_script_ctx *ctx = call->ctx;
+
+ if (file->seq == call->seq) {
+ if (context)
+ ctx->handle_error(ctx, "Recursive include", context);
+
+ return;
+ }
+
+ file->seq = call->seq;
+ while (file) {
+ json_process_cmd(call, file->data);
+ file = file->next;
+ }
+}
+
+const char *json_script_find_var(struct json_script_ctx *ctx, struct blob_attr *vars,
+ const char *name)
+{
+ struct blob_attr *cur;
+ int rem;
+
+ blobmsg_for_each_attr(cur, vars, rem) {
+ if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
+ continue;
+
+ if (strcmp(blobmsg_name(cur), name) != 0)
+ continue;
+
+ return blobmsg_data(cur);
+ }
+
+ return ctx->handle_var(ctx, name, vars);
+}
+
+static const char *
+msg_find_var(struct json_call *call, const char *name)
+{
+ return json_script_find_var(call->ctx, call->vars, name);
+}
+
+static void
+json_get_tuple(struct blob_attr *cur, struct blob_attr **tb, int t1, int t2)
+{
+ static struct blobmsg_policy expr_tuple[3] = {
+ { .type = BLOBMSG_TYPE_STRING },
+ {},
+ {},
+ };
+
+ expr_tuple[1].type = t1;
+ expr_tuple[2].type = t2;
+ blobmsg_parse_array(expr_tuple, 3, tb, blobmsg_data(cur), blobmsg_data_len(cur));
+}
+
+static int handle_if(struct json_call *call, struct blob_attr *expr)
+{
+ struct blob_attr *tb[4];
+ int ret;
+
+ static const struct blobmsg_policy if_tuple[4] = {
+ { .type = BLOBMSG_TYPE_STRING },
+ { .type = BLOBMSG_TYPE_ARRAY },
+ { .type = BLOBMSG_TYPE_ARRAY },
+ { .type = BLOBMSG_TYPE_ARRAY },
+ };
+
+ blobmsg_parse_array(if_tuple, 4, tb, blobmsg_data(expr), blobmsg_data_len(expr));
+
+ if (!tb[1] || !tb[2])
+ return 0;
+
+ ret = json_process_expr(call, tb[1]);
+ if (ret < 0)
+ return 0;
+
+ if (ret)
+ return json_process_cmd(call, tb[2]);
+
+ if (!tb[3])
+ return 0;
+
+ return json_process_cmd(call, tb[3]);
+}
+
+static int handle_case(struct json_call *call, struct blob_attr *expr)
+{
+ struct blob_attr *tb[3], *cur;
+ const char *var;
+ int rem;
+
+ json_get_tuple(expr, tb, BLOBMSG_TYPE_STRING, BLOBMSG_TYPE_TABLE);
+ if (!tb[1] || !tb[2])
+ return 0;
+
+ var = msg_find_var(call, blobmsg_data(tb[1]));
+ if (!var)
+ return 0;
+
+ blobmsg_for_each_attr(cur, tb[2], rem) {
+ if (!strcmp(var, blobmsg_name(cur)))
+ return json_process_cmd(call, cur);
+ }
+
+ return 0;
+}
+
+static int handle_return(struct json_call *call, struct blob_attr *expr)
+{
+ return -2;
+}
+
+static int handle_include(struct json_call *call, struct blob_attr *expr)
+{
+ struct blob_attr *tb[3];
+ struct json_script_file *f;
+
+ json_get_tuple(expr, tb, BLOBMSG_TYPE_STRING, 0);
+ if (!tb[1])
+ return 0;
+
+ f = json_script_get_file(call->ctx, blobmsg_data(tb[1]));
+ if (!f)
+ return 0;
+
+ __json_script_run(call, f, expr);
+ return 0;
+}
+
+static const struct json_handler cmd[] = {
+ { "if", handle_if },
+ { "case", handle_case },
+ { "return", handle_return },
+ { "include", handle_include },
+};
+
+static int eq_regex_cmp(const char *str, const char *pattern, bool regex)
+{
+ regex_t reg;
+ int ret;
+
+ if (!regex)
+ return !strcmp(str, pattern);
+
+ if (regcomp(®, pattern, REG_EXTENDED | REG_NOSUB))
+ return 0;
+
+ ret = !regexec(®, str, 0, NULL, 0);
+ regfree(®);
+
+ return ret;
+}
+
+static int expr_eq_regex(struct json_call *call, struct blob_attr *expr, bool regex)
+{
+ struct json_script_ctx *ctx = call->ctx;
+ struct blob_attr *tb[3], *cur;
+ const char *var;
+ int rem;
+
+ json_get_tuple(expr, tb, BLOBMSG_TYPE_STRING, 0);
+ if (!tb[1] || !tb[2])
+ return -1;
+
+ var = msg_find_var(call, blobmsg_data(tb[1]));
+ if (!var)
+ return 0;
+
+ switch(blobmsg_type(tb[2])) {
+ case BLOBMSG_TYPE_STRING:
+ return eq_regex_cmp(var, blobmsg_data(tb[2]), regex);
+ case BLOBMSG_TYPE_ARRAY:
+ blobmsg_for_each_attr(cur, tb[2], rem) {
+ if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING) {
+ ctx->handle_error(ctx, "Unexpected element type", cur);
+ return -1;
+ }
+
+ if (eq_regex_cmp(var, blobmsg_data(cur), regex))
+ return 1;
+ }
+ return 0;
+ default:
+ ctx->handle_error(ctx, "Unexpected element type", tb[2]);
+ return -1;
+ }
+}
+
+static int handle_expr_eq(struct json_call *call, struct blob_attr *expr)
+{
+ return expr_eq_regex(call, expr, false);
+}
+
+static int handle_expr_regex(struct json_call *call, struct blob_attr *expr)
+{
+ return expr_eq_regex(call, expr, true);
+}
+
+static int handle_expr_has(struct json_call *call, struct blob_attr *expr)
+{
+ struct json_script_ctx *ctx = call->ctx;
+ struct blob_attr *tb[3], *cur;
+ int rem;
+
+ json_get_tuple(expr, tb, 0, 0);
+ if (!tb[1])
+ return -1;
+
+ switch(blobmsg_type(tb[1])) {
+ case BLOBMSG_TYPE_STRING:
+ return !!msg_find_var(call, blobmsg_data(tb[1]));
+ case BLOBMSG_TYPE_ARRAY:
+ blobmsg_for_each_attr(cur, tb[1], rem) {
+ if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING) {
+ ctx->handle_error(ctx, "Unexpected element type", cur);
+ return -1;
+ }
+
+ if (msg_find_var(call, blobmsg_data(cur)))
+ return 1;
+ }
+ return 0;
+ default:
+ ctx->handle_error(ctx, "Unexpected element type", tb[1]);
+ return -1;
+ }
+}
+
+static int expr_and_or(struct json_call *call, struct blob_attr *expr, bool and)
+{
+ struct blob_attr *cur;
+ int ret, rem;
+ int i = 0;
+
+ blobmsg_for_each_attr(cur, expr, rem) {
+ if (i++ < 1)
+ continue;
+
+ ret = json_process_expr(call, cur);
+ if (ret < 0)
+ return ret;
+
+ if (ret != and)
+ return ret;
+ }
+
+ return and;
+}
+
+static int handle_expr_and(struct json_call *call, struct blob_attr *expr)
+{
+ return expr_and_or(call, expr, 1);
+}
+
+static int handle_expr_or(struct json_call *call, struct blob_attr *expr)
+{
+ return expr_and_or(call, expr, 0);
+}
+
+static int handle_expr_not(struct json_call *call, struct blob_attr *expr)
+{
+ struct blob_attr *tb[3];
+
+ json_get_tuple(expr, tb, BLOBMSG_TYPE_ARRAY, 0);
+ if (!tb[1])
+ return -1;
+
+ return json_process_expr(call, tb[1]);
+}
+
+static const struct json_handler expr[] = {
+ { "eq", handle_expr_eq },
+ { "regex", handle_expr_regex },
+ { "has", handle_expr_has },
+ { "and", handle_expr_and },
+ { "or", handle_expr_or },
+ { "not", handle_expr_not },
+};
+
+static int
+__json_process_type(struct json_call *call, struct blob_attr *cur,
+ const struct json_handler *h, int n, bool *found)
+{
+ const char *name = blobmsg_data(blobmsg_data(cur));
+ int i;
+
+ for (i = 0; i < n; i++) {
+ if (strcmp(name, h[i].name) != 0)
+ continue;
+
+ *found = true;
+ return h[i].cb(call, cur);
+ }
+
+ *found = false;
+ return -1;
+}
+
+static int json_process_expr(struct json_call *call, struct blob_attr *cur)
+{
+ struct json_script_ctx *ctx = call->ctx;
+ bool found;
+ int ret;
+
+ if (blobmsg_type(cur) != BLOBMSG_TYPE_ARRAY ||
+ blobmsg_type(blobmsg_data(cur)) != BLOBMSG_TYPE_STRING) {
+ ctx->handle_error(ctx, "Unexpected element type", cur);
+ return -1;
+ }
+
+ ret = __json_process_type(call, cur, expr, ARRAY_SIZE(expr), &found);
+ if (!found)
+ ctx->handle_error(ctx, "Unknown expression type", cur);
+
+ return ret;
+}
+
+static int cmd_add_string(struct json_call *call, const char *pattern)
+{
+ struct json_script_ctx *ctx = call->ctx;
+ char *dest, *next, *str;
+ int len = 0;
+ bool var = false;
+ char c = '%';
+
+ dest = blobmsg_alloc_string_buffer(&ctx->buf, NULL, 1);
+ next = alloca(strlen(pattern) + 1);
+ strcpy(next, pattern);
+
+ for (str = next; str; str = next) {
+ const char *cur;
+ char *end;
+ int cur_len = 0;
+ bool cur_var = var;
+
+ end = strchr(str, '%');
+ if (end) {
+ *end = 0;
+ next = end + 1;
+ var = !var;
+ } else {
+ end = str + strlen(str);
+ next = NULL;
+ }
+
+ if (cur_var) {
+ if (next > str) {
+ cur = msg_find_var(call, str);
+ if (!cur)
+ continue;
+
+ cur_len = strlen(cur);
+ } else {
+ cur = &c;
+ cur_len = 1;
+ }
+ } else {
+ if (str == end)
+ continue;
+
+ cur = str;
+ cur_len = end - str;
+ }
+
+ dest = blobmsg_realloc_string_buffer(&ctx->buf, cur_len + 1);
+ memcpy(dest + len, cur, cur_len);
+ len += cur_len;
+ }
+
+ if (var)
+ return -1;
+
+ dest[len] = 0;
+ blobmsg_add_string_buffer(&ctx->buf);
+ return 0;
+}
+
+static int cmd_process_strings(struct json_call *call, struct blob_attr *attr)
+{
+ struct json_script_ctx *ctx = call->ctx;
+ struct blob_attr *cur;
+ int args = -1;
+ int rem, ret;
+ void *c;
+
+ blob_buf_init(&ctx->buf, 0);
+ c = blobmsg_open_array(&ctx->buf, NULL);
+ blobmsg_for_each_attr(cur, attr, rem) {
+ if (args++ < 0)
+ continue;
+
+ if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING) {
+ ctx->handle_error(ctx, "Invalid argument in command", attr);
+ return -1;
+ }
+
+ ret = cmd_add_string(call, blobmsg_data(cur));
+ if (ret) {
+ ctx->handle_error(ctx, "Unterminated variable reference in string", attr);
+ return ret;
+ }
+ }
+
+ blobmsg_close_array(&ctx->buf, c);
+
+ return 0;
+}
+
+static int __json_process_cmd(struct json_call *call, struct blob_attr *cur)
+{
+ struct json_script_ctx *ctx = call->ctx;
+ const char *name;
+ bool found;
+ int ret;
+
+ if (blobmsg_type(cur) != BLOBMSG_TYPE_ARRAY ||
+ blobmsg_type(blobmsg_data(cur)) != BLOBMSG_TYPE_STRING) {
+ ctx->handle_error(ctx, "Unexpected element type", cur);
+ return -1;
+ }
+
+ ret = __json_process_type(call, cur, cmd, ARRAY_SIZE(cmd), &found);
+ if (found)
+ return ret;
+
+ name = blobmsg_data(blobmsg_data(cur));
+ ret = cmd_process_strings(call, cur);
+ if (ret)
+ return ret;
+
+ ctx->handle_command(ctx, name, blob_data(ctx->buf.head), call->vars);
+
+ return 0;
+}
+
+static int json_process_cmd(struct json_call *call, struct blob_attr *block)
+{
+ struct json_script_ctx *ctx = call->ctx;
+ struct blob_attr *cur;
+ int rem;
+ int ret;
+ int i = 0;
+
+ if (blobmsg_type(block) != BLOBMSG_TYPE_ARRAY) {
+ ctx->handle_error(ctx, "Unexpected element type", block);
+ return -1;
+ }
+
+ blobmsg_for_each_attr(cur, block, rem) {
+ switch(blobmsg_type(cur)) {
+ case BLOBMSG_TYPE_STRING:
+ if (!i)
+ return __json_process_cmd(call, block);
+ default:
+ ret = json_process_cmd(call, cur);
+ if (ret < -1)
+ return ret;
+ break;
+ }
+ i++;
+ }
+
+ return 0;
+}
+
+void json_script_run(struct json_script_ctx *ctx, const char *name,
+ struct blob_attr *vars)
+{
+ struct json_script_file *file;
+ static unsigned int _seq = 0;
+ struct json_call call = {
+ .ctx = ctx,
+ .vars = vars,
+ .seq = ++_seq,
+ };
+
+ /* overflow */
+ if (!call.seq)
+ call.seq = ++_seq;
+
+ file = json_script_get_file(ctx, name);
+ if (!file)
+ return;
+
+ __json_script_run(&call, file, NULL);
+}
+
+static void __json_script_file_free(struct json_script_ctx *ctx, struct json_script_file *f)
+{
+ struct json_script_file *next;
+
+ for (next = f->next; f; f = next, next = f->next)
+ free(f);
+}
+
+void
+json_script_free(struct json_script_ctx *ctx)
+{
+ struct json_script_file *f, *next;
+
+ avl_remove_all_elements(&ctx->files, f, avl, next)
+ __json_script_file_free(ctx, f);
+
+ blob_buf_free(&ctx->buf);
+}
+
+static void
+__default_handle_error(struct json_script_ctx *ctx, const char *msg,
+ struct blob_attr *context)
+{
+}
+
+static const char *
+__default_handle_var(struct json_script_ctx *ctx, const char *name,
+ struct blob_attr *vars)
+{
+ return NULL;
+}
+
+static int
+__default_handle_expr(struct json_script_ctx *ctx, const char *name,
+ struct blob_attr *expr, struct blob_attr *vars)
+{
+ return -1;
+}
+
+static struct json_script_file *
+__default_handle_file(struct json_script_ctx *ctx, const char *name)
+{
+ return NULL;
+}
+
+void json_script_init(struct json_script_ctx *ctx)
+{
+ avl_init(&ctx->files, avl_strcmp, false, NULL);
+
+ if (!ctx->handle_error)
+ ctx->handle_error = __default_handle_error;
+
+ if (!ctx->handle_var)
+ ctx->handle_var = __default_handle_var;
+
+ if (!ctx->handle_expr)
+ ctx->handle_expr = __default_handle_expr;
+
+ if (!ctx->handle_file)
+ ctx->handle_file = __default_handle_file;
+}
--- /dev/null
+/*
+ * Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+#ifndef __JSON_SCRIPT_H
+#define __JSON_SCRIPT_H
+
+#include <libubox/avl.h>
+#include <libubox/blob.h>
+#include <libubox/blobmsg.h>
+#include <libubox/utils.h>
+
+struct json_script_file;
+
+struct json_script_ctx {
+ struct avl_tree files;
+ struct blob_buf buf;
+
+ uint32_t run_seq;
+
+ /*
+ * handle_command: handle a command that was not recognized by the
+ * json_script core (required)
+ *
+ * @cmd: blobmsg container of the processed command
+ * @vars: blobmsg container of current run variables
+ */
+ void (*handle_command)(struct json_script_ctx *ctx, const char *name,
+ struct blob_attr *cmd, struct blob_attr *vars);
+
+ /*
+ * handle_expr: handle an expression that was not recognized by the
+ * json_script core (optional)
+ *
+ * @expr: blobmsg container of the processed expression
+ * @vars: blobmsg container of current runtime variables
+ */
+ int (*handle_expr)(struct json_script_ctx *ctx, const char *name,
+ struct blob_attr *expr, struct blob_attr *vars);
+
+ /*
+ * handle_var - look up a variable that's not part of the runtime
+ * variable set (optional)
+ */
+ const char *(*handle_var)(struct json_script_ctx *ctx, const char *name,
+ struct blob_attr *vars);
+
+ /*
+ * handle_file - load a file by filename (optional)
+ *
+ * in case of wildcards, it can return a chain of json_script files
+ * linked via the ::next pointer. Only the first json_script file is
+ * added to the tree.
+ */
+ struct json_script_file *(*handle_file)(struct json_script_ctx *ctx,
+ const char *name);
+
+ /*
+ * handle_error - handle a processing error in a command or expression
+ * (optional)
+ *
+ * @msg: error message
+ * @context: source file context of the error (blobmsg container)
+ */
+ void (*handle_error)(struct json_script_ctx *ctx, const char *msg,
+ struct blob_attr *context);
+};
+
+struct json_script_file {
+ struct avl_node avl;
+ struct json_script_file *next;
+
+ unsigned int seq;
+ struct blob_attr data[];
+};
+
+void json_script_init(struct json_script_ctx *ctx);
+void json_script_free(struct json_script_ctx *ctx);
+
+/*
+ * json_script_run - run a json script with a set of runtime variables
+ *
+ * @filename: initial filename to run
+ * @vars: blobmsg container of the current runtime variables
+ */
+void json_script_run(struct json_script_ctx *ctx, const char *filename,
+ struct blob_attr *vars);
+
+struct json_script_file *
+json_script_file_from_blobmsg(const char *name, void *data, int len);
+
+/*
+ * json_script_find_var - helper function to find a runtime variable from
+ * the list passed by json_script user.
+ * It is intended to be used by the .handle_var callback
+ */
+const char *json_script_find_var(struct json_script_ctx *ctx, struct blob_attr *vars,
+ const char *name);
+
+#endif
projects / oweals / libubox.git / commitdiff