1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
|
/*
* extsprintf.js: extended POSIX-style sprintf
*/
var mod_assert = require('assert');
var mod_util = require('util');
/*
* Public interface
*/
exports.sprintf = jsSprintf;
exports.printf = jsPrintf;
exports.fprintf = jsFprintf;
/*
* Stripped down version of s[n]printf(3c). We make a best effort to throw an
* exception when given a format string we don't understand, rather than
* ignoring it, so that we won't break existing programs if/when we go implement
* the rest of this.
*
* This implementation currently supports specifying
* - field alignment ('-' flag),
* - zero-pad ('0' flag)
* - always show numeric sign ('+' flag),
* - field width
* - conversions for strings, decimal integers, and floats (numbers).
* - argument size specifiers. These are all accepted but ignored, since
* Javascript has no notion of the physical size of an argument.
*
* Everything else is currently unsupported, most notably precision, unsigned
* numbers, non-decimal numbers, and characters.
*/
function jsSprintf(fmt)
{
var regex = [
'([^%]*)', /* normal text */
'%', /* start of format */
'([\'\\-+ #0]*?)', /* flags (optional) */
'([1-9]\\d*)?', /* width (optional) */
'(\\.([1-9]\\d*))?', /* precision (optional) */
'[lhjztL]*?', /* length mods (ignored) */
'([diouxXfFeEgGaAcCsSp%jr])' /* conversion */
].join('');
var re = new RegExp(regex);
var args = Array.prototype.slice.call(arguments, 1);
var flags, width, precision, conversion;
var left, pad, sign, arg, match;
var ret = '';
var argn = 1;
mod_assert.equal('string', typeof (fmt));
while ((match = re.exec(fmt)) !== null) {
ret += match[1];
fmt = fmt.substring(match[0].length);
flags = match[2] || '';
width = match[3] || 0;
precision = match[4] || '';
conversion = match[6];
left = false;
sign = false;
pad = ' ';
if (conversion == '%') {
ret += '%';
continue;
}
if (args.length === 0)
throw (new Error('too few args to sprintf'));
arg = args.shift();
argn++;
if (flags.match(/[\' #]/))
throw (new Error(
'unsupported flags: ' + flags));
if (precision.length > 0)
throw (new Error(
'non-zero precision not supported'));
if (flags.match(/-/))
left = true;
if (flags.match(/0/))
pad = '0';
if (flags.match(/\+/))
sign = true;
switch (conversion) {
case 's':
if (arg === undefined || arg === null)
throw (new Error('argument ' + argn +
': attempted to print undefined or null ' +
'as a string'));
ret += doPad(pad, width, left, arg.toString());
break;
case 'd':
arg = Math.floor(arg);
/*jsl:fallthru*/
case 'f':
sign = sign && arg > 0 ? '+' : '';
ret += sign + doPad(pad, width, left,
arg.toString());
break;
case 'x':
ret += doPad(pad, width, left, arg.toString(16));
break;
case 'j': /* non-standard */
if (width === 0)
width = 10;
ret += mod_util.inspect(arg, false, width);
break;
case 'r': /* non-standard */
ret += dumpException(arg);
break;
default:
throw (new Error('unsupported conversion: ' +
conversion));
}
}
ret += fmt;
return (ret);
}
function jsPrintf() {
var args = Array.prototype.slice.call(arguments);
args.unshift(process.stdout);
jsFprintf.apply(null, args);
}
function jsFprintf(stream) {
var args = Array.prototype.slice.call(arguments, 1);
return (stream.write(jsSprintf.apply(this, args)));
}
function doPad(chr, width, left, str)
{
var ret = str;
while (ret.length < width) {
if (left)
ret += chr;
else
ret = chr + ret;
}
return (ret);
}
/*
* This function dumps long stack traces for exceptions having a cause() method.
* See node-verror for an example.
*/
function dumpException(ex)
{
var ret;
if (!(ex instanceof Error))
throw (new Error(jsSprintf('invalid type for %%r: %j', ex)));
/* Note that V8 prepends "ex.stack" with ex.toString(). */
ret = 'EXCEPTION: ' + ex.constructor.name + ': ' + ex.stack;
if (ex.cause && typeof (ex.cause) === 'function') {
var cex = ex.cause();
if (cex) {
ret += '\nCaused by: ' + dumpException(cex);
}
}
return (ret);
}
|
