Add example/jsonptr -strict-json-pointer-syntax
diff --git a/example/jsonptr/jsonptr.cc b/example/jsonptr/jsonptr.cc
index 3345b57..1486c70 100644
--- a/example/jsonptr/jsonptr.cc
+++ b/example/jsonptr/jsonptr.cc
@@ -121,6 +121,7 @@
" -i=NUM -indent=NUM\n"
" -o=NUM -max-output-depth=NUM\n"
" -q=STR -query=STR\n"
+ " -s -strict-json-pointer-syntax\n"
" -t -tabs\n"
" -fail-if-unsandboxed\n"
"\n"
@@ -167,13 +168,20 @@
"object has multiple \"foo\" children but the first one doesn't have a\n"
"\"bar\" child, even if later ones do.\n"
"\n"
+ "The -s or -strict-json-pointer-syntax flag restricts the -query=STR\n"
+ "string to exactly RFC 6901, with only two escape sequences: \"~0\" and\n"
+ "\"~1\" for \"~\" and \"/\". Without this flag, this program also lets\n"
+ "\"~n\" and \"~r\" escape the New Line and Carriage Return ASCII control\n"
+ "characters, which can work better with line oriented Unix tools that\n"
+ "assume exactly one value (i.e. one JSON Pointer string) per line.\n"
+ "\n"
"----\n"
"\n"
"The -o=NUM or -max-output-depth=NUM flag gives the maximum (inclusive)\n"
"output depth. JSON containers ([] arrays and {} objects) can hold other\n"
"containers. When this flag is set, containers at depth NUM are replaced\n"
"with \"[…]\" or \"{…}\". A bare -o or -max-output-depth is equivalent to\n"
- "NUM=1. The flag's absence is equivalent to an unlimited output depth.\n"
+ "-o=1. The flag's absence is equivalent to an unlimited output depth.\n"
"\n"
"The -max-output-depth flag only affects the program's output. It doesn't\n"
"affect whether or not the input is considered valid JSON. The JSON\n"
@@ -413,6 +421,14 @@
if (*ptr != '/') {
break;
}
+ } else if (*j == 'n') {
+ if (*ptr != '\n') {
+ break;
+ }
+ } else if (*j == 'r') {
+ if (*ptr != '\r') {
+ break;
+ }
} else {
break;
}
@@ -445,8 +461,11 @@
// validate returns whether the (ptr, len) arguments form a valid JSON
// Pointer. In particular, it must be valid UTF-8, and either be empty or
// start with a '/'. Any '~' within must immediately be followed by either
- // '0' or '1'.
- static bool validate(char* query_c_string, size_t length) {
+ // '0' or '1'. If strict_json_pointer_syntax is false, a '~' may also be
+ // followed by either 'n' or 'r'.
+ static bool validate(char* query_c_string,
+ size_t length,
+ bool strict_json_pointer_syntax) {
if (length <= 0) {
return true;
}
@@ -461,11 +480,24 @@
if (!o.is_valid()) {
return false;
}
- if (previous_was_tilde && (o.code_point != '0') &&
- (o.code_point != '1')) {
- return false;
+
+ if (previous_was_tilde) {
+ switch (o.code_point) {
+ case '0':
+ case '1':
+ break;
+ case 'n':
+ case 'r':
+ if (strict_json_pointer_syntax) {
+ return false;
+ }
+ break;
+ default:
+ return false;
+ }
}
previous_was_tilde = o.code_point == '~';
+
s.ptr += o.byte_length;
s.len -= o.byte_length;
}
@@ -484,6 +516,7 @@
size_t indent;
uint32_t max_output_depth;
char* query_c_string;
+ bool strict_json_pointer_syntax;
bool tabs;
} flags = {0};
@@ -547,11 +580,12 @@
if (!strncmp(arg, "q=", 2) || !strncmp(arg, "query=", 6)) {
while (*arg++ != '=') {
}
- if (Query::validate(arg, strlen(arg))) {
- flags.query_c_string = arg;
- continue;
- }
- return usage;
+ flags.query_c_string = arg;
+ continue;
+ }
+ if (!strcmp(arg, "s") || !strcmp(arg, "strict-json-pointer-syntax")) {
+ flags.strict_json_pointer_syntax = true;
+ continue;
}
if (!strcmp(arg, "t") || !strcmp(arg, "tabs")) {
flags.tabs = true;
@@ -561,6 +595,12 @@
return usage;
}
+ if (flags.query_c_string &&
+ !Query::validate(flags.query_c_string, strlen(flags.query_c_string),
+ flags.strict_json_pointer_syntax)) {
+ return "main: bad JSON Pointer (RFC 6901) syntax for the -query=STR flag";
+ }
+
flags.remaining_argc = argc - c;
flags.remaining_argv = argv + c;
return nullptr;
