Add JSON syntax highlighting

This commit is contained in:
Přemysl Eric Janouch 2016-01-21 07:34:03 +01:00
parent d6d53a4e70
commit e70cd4e434
2 changed files with 326 additions and 16 deletions

View File

@ -1,4 +1,4 @@
Copyright (c) 2014, 2015, Přemysl Janouch <p.janouch@gmail.com>
Copyright (c) 2014 - 2016, Přemysl Janouch <p.janouch@gmail.com>
All rights reserved.
Permission to use, copy, modify, and/or distribute this software for any

View File

@ -1,7 +1,7 @@
/*
* json-rpc-shell.c: simple JSON-RPC 2.0 shell
*
* Copyright (c) 2014 - 2015, Přemysl Janouch <p.janouch@gmail.com>
* Copyright (c) 2014 - 2016, Přemysl Janouch <p.janouch@gmail.com>
* All rights reserved.
*
* Permission to use, copy, modify, and/or distribute this software for any
@ -28,7 +28,12 @@
XX( WARNING, "warning", "Terminal attrs for warnings" ) \
XX( ERROR, "error", "Terminal attrs for errors" ) \
XX( INCOMING, "incoming", "Terminal attrs for incoming traffic" ) \
XX( OUTGOING, "outgoing", "Terminal attrs for outgoing traffic" )
XX( OUTGOING, "outgoing", "Terminal attrs for outgoing traffic" ) \
XX( JSON_FIELD, "json_field", "Terminal attrs for JSON field names" ) \
XX( JSON_NULL, "json_null", "Terminal attrs for JSON null values" ) \
XX( JSON_BOOL, "json_bool", "Terminal attrs for JSON booleans" ) \
XX( JSON_NUMBER, "json_number", "Terminal attrs for JSON numbers" ) \
XX( JSON_STRING, "json_string", "Terminal attrs for JSON strings" )
enum
{
@ -1171,21 +1176,31 @@ init_colors (struct app_context *ctx)
// Use escape sequences from terminfo if possible, and SGR as a fallback
if (init_terminal ())
{
INIT_ATTR (PROMPT, enter_bold_mode);
INIT_ATTR (RESET, exit_attribute_mode);
INIT_ATTR (WARNING, g_terminal.color_set[COLOR_YELLOW]);
INIT_ATTR (ERROR, g_terminal.color_set[COLOR_RED]);
INIT_ATTR (INCOMING, "");
INIT_ATTR (OUTGOING, "");
INIT_ATTR (PROMPT, enter_bold_mode);
INIT_ATTR (RESET, exit_attribute_mode);
INIT_ATTR (WARNING, g_terminal.color_set[COLOR_YELLOW]);
INIT_ATTR (ERROR, g_terminal.color_set[COLOR_RED]);
INIT_ATTR (INCOMING, "");
INIT_ATTR (OUTGOING, "");
INIT_ATTR (JSON_FIELD, enter_bold_mode);
INIT_ATTR (JSON_NULL, g_terminal.color_set[COLOR_CYAN]);
INIT_ATTR (JSON_BOOL, g_terminal.color_set[COLOR_RED]);
INIT_ATTR (JSON_NUMBER, g_terminal.color_set[COLOR_MAGENTA]);
INIT_ATTR (JSON_STRING, g_terminal.color_set[COLOR_BLUE]);
}
else
{
INIT_ATTR (PROMPT, "\x1b[1m");
INIT_ATTR (RESET, "\x1b[0m");
INIT_ATTR (WARNING, "\x1b[33m");
INIT_ATTR (ERROR, "\x1b[31m");
INIT_ATTR (INCOMING, "");
INIT_ATTR (OUTGOING, "");
INIT_ATTR (PROMPT, "\x1b[1m");
INIT_ATTR (RESET, "\x1b[0m");
INIT_ATTR (WARNING, "\x1b[33m");
INIT_ATTR (ERROR, "\x1b[31m");
INIT_ATTR (INCOMING, "");
INIT_ATTR (OUTGOING, "");
INIT_ATTR (JSON_FIELD, "\x1b[1m");
INIT_ATTR (JSON_NULL, "\x1b[36m");
INIT_ATTR (JSON_BOOL, "\x1b[31m");
INIT_ATTR (JSON_NUMBER, "\x1b[35m");
INIT_ATTR (JSON_STRING, "\x1b[32m");
}
#undef INIT_ATTR
@ -2387,6 +2402,298 @@ backend_curl_new (struct app_context *ctx, const char *endpoint)
return &self->super;
}
// --- JSON tokenizer ----------------------------------------------------------
// A dumb JSON tokenizer intended strictly just for syntax highlighting
//
// TODO: return also escape squences as a special token class (-> state)
enum jtoken
{
JTOKEN_EOF, ///< End of input
JTOKEN_ERROR, ///< EOF or error
JTOKEN_WHITESPACE, ///< Whitespace
JTOKEN_LBRACKET, ///< Left bracket
JTOKEN_RBRACKET, ///< Right bracket
JTOKEN_LBRACE, ///< Left curly bracket
JTOKEN_RBRACE, ///< Right curly bracket
JTOKEN_COLON, ///< Colon
JTOKEN_COMMA, ///< Comma
JTOKEN_NULL, ///< null
JTOKEN_BOOLEAN, ///< true, false
JTOKEN_NUMBER, ///< Number
JTOKEN_STRING ///< String
};
struct jtokenizer
{
const char *p; ///< Current position in input
size_t len; ///< How many bytes of input are left
struct str chunk; ///< Parsed chunk
};
static void
jtokenizer_init (struct jtokenizer *self, const char *p, size_t len)
{
self->p = p;
self->len = len;
str_init (&self->chunk);
}
static void
jtokenizer_free (struct jtokenizer *self)
{
str_free (&self->chunk);
}
static void
jtokenizer_advance (struct jtokenizer *self, size_t n)
{
str_append_data (&self->chunk, self->p, n);
self->p += n;
self->len -= n;
}
static int
jtokenizer_accept (struct jtokenizer *self, const char *chars)
{
if (!self->len || !strchr (chars, *self->p))
return false;
jtokenizer_advance (self, 1);
return true;
}
static bool
jtokenizer_ws (struct jtokenizer *self)
{
size_t len = 0;
while (jtokenizer_accept (self, "\t\r\n "))
len++;
return len != 0;
}
static bool
jtokenizer_word (struct jtokenizer *self, const char *word)
{
size_t len = strlen (word);
if (self->len < len || memcmp (self->p, word, len))
return false;
jtokenizer_advance (self, len);
return true;
}
static bool
jtokenizer_escape_sequence (struct jtokenizer *self)
{
if (!self->len)
return false;
if (jtokenizer_accept (self, "u"))
{
for (int i = 0; i < 4; i++)
if (!jtokenizer_accept (self, "0123456789abcdefABCDEF"))
return false;
return true;
}
return jtokenizer_accept (self, "\"\\/bfnrt");
}
static bool
jtokenizer_string (struct jtokenizer *self)
{
while (self->len)
{
unsigned char c = *self->p;
jtokenizer_advance (self, 1);
if (c == '"')
return true;
if (c == '\\' && !jtokenizer_escape_sequence (self))
return false;
}
return false;
}
static bool
jtokenizer_integer (struct jtokenizer *self)
{
size_t len = 0;
while (jtokenizer_accept (self, "0123456789"))
len++;
return len != 0;
}
static bool
jtokenizer_number (struct jtokenizer *self)
{
(void) jtokenizer_accept (self, "-");
if (!self->len)
return false;
if (!jtokenizer_accept (self, "0")
&& !jtokenizer_integer (self))
return false;
if (jtokenizer_accept (self, ".")
&& !jtokenizer_integer (self))
return false;
if (jtokenizer_accept (self, "eE"))
{
(void) jtokenizer_accept (self, "+-");
if (!jtokenizer_integer (self))
return false;
}
return true;
}
static enum jtoken
jtokenizer_next (struct jtokenizer *self)
{
str_reset (&self->chunk);
if (!self->len) return JTOKEN_EOF;
if (jtokenizer_ws (self)) return JTOKEN_WHITESPACE;
if (jtokenizer_accept (self, "[")) return JTOKEN_LBRACKET;
if (jtokenizer_accept (self, "]")) return JTOKEN_RBRACKET;
if (jtokenizer_accept (self, "{")) return JTOKEN_LBRACE;
if (jtokenizer_accept (self, "}")) return JTOKEN_RBRACE;
if (jtokenizer_accept (self, ":")) return JTOKEN_COLON;
if (jtokenizer_accept (self, ",")) return JTOKEN_COMMA;
if (jtokenizer_word (self, "null")) return JTOKEN_NULL;
if (jtokenizer_word (self, "true")
|| jtokenizer_word (self, "false")) return JTOKEN_BOOLEAN;
if (jtokenizer_accept (self, "\""))
{
if (jtokenizer_string (self)) return JTOKEN_STRING;
}
else if (jtokenizer_number (self)) return JTOKEN_NUMBER;
jtokenizer_advance (self, self->len);
return JTOKEN_ERROR;
}
// --- JSON highlighter --------------------------------------------------------
// Currently errors in parsing only mean that the rest doesn't get highlighted
struct json_highlight
{
struct app_context *ctx; ///< Application context
struct jtokenizer tokenizer; ///< Tokenizer
FILE *output; ///< Output handle
};
static void
json_highlight_print (struct json_highlight *self, int attr)
{
print_attributed (self->ctx, self->output, attr,
"%s", self->tokenizer.chunk.str);
}
static void json_highlight_value
(struct json_highlight *self, enum jtoken token);
static void
json_highlight_object (struct json_highlight *self)
{
// Distinguishing field names from regular string values in objects
bool in_field_name = true;
enum jtoken token;
while ((token = jtokenizer_next (&self->tokenizer)))
switch (token)
{
case JTOKEN_COLON:
in_field_name = false;
json_highlight_value (self, token);
break;
case JTOKEN_COMMA:
in_field_name = true;
json_highlight_value (self, token);
break;
case JTOKEN_STRING:
if (in_field_name)
json_highlight_print (self, ATTR_JSON_FIELD);
else
json_highlight_print (self, ATTR_JSON_STRING);
break;
case JTOKEN_RBRACE:
json_highlight_value (self, token);
return;
default:
json_highlight_value (self, token);
}
}
static void
json_highlight_array (struct json_highlight *self)
{
enum jtoken token;
while ((token = jtokenizer_next (&self->tokenizer)))
switch (token)
{
case JTOKEN_RBRACKET:
json_highlight_value (self, token);
return;
default:
json_highlight_value (self, token);
}
}
static void
json_highlight_value (struct json_highlight *self, enum jtoken token)
{
switch (token)
{
case JTOKEN_LBRACE:
json_highlight_print (self, ATTR_INCOMING);
json_highlight_object (self);
break;
case JTOKEN_LBRACKET:
json_highlight_print (self, ATTR_INCOMING);
json_highlight_array (self);
break;
case JTOKEN_NULL:
json_highlight_print (self, ATTR_JSON_NULL);
break;
case JTOKEN_BOOLEAN:
json_highlight_print (self, ATTR_JSON_BOOL);
break;
case JTOKEN_NUMBER:
json_highlight_print (self, ATTR_JSON_NUMBER);
break;
case JTOKEN_STRING:
json_highlight_print (self, ATTR_JSON_STRING);
break;
default:
json_highlight_print (self, ATTR_INCOMING);
}
}
static void
json_highlight (struct app_context *ctx, const char *s, FILE *output)
{
struct json_highlight self = { .ctx = ctx, .output = output };
jtokenizer_init (&self.tokenizer, s, strlen (s));
// There should be at maximum one value in the input however,
// but let's just keep on going and process it all
enum jtoken token;
while ((token = jtokenizer_next (&self.tokenizer)))
json_highlight_value (&self, token);
jtokenizer_free (&self.tokenizer);
}
// --- Main program ------------------------------------------------------------
static void
@ -2497,7 +2804,10 @@ parse_response (struct app_context *ctx, struct str *buf)
if (!s)
print_error ("character conversion failed for `%s'", "result");
else
print_attributed (ctx, stdout, ATTR_INCOMING, "%s\n", s);
{
json_highlight (ctx, s, stdout);
fputc ('\n', stdout);
}
free (s);
}