1 /* Copyright (c) 2002-2006 Lucent Technologies; see LICENSE */
2 #include <stdarg.h>
3 #include <string.h>
4 #include <stdatomic.h>
5 #include "plan9.h"
6 #include "fmt.h"
7 #include "fmtdef.h"
8 
9 enum
10 {
11 	Maxfmt = 128
12 };
13 
14 typedef struct Convfmt Convfmt;
15 struct Convfmt
16 {
17 	int	c;
18 	Fmts	fmt;
19 };
20 
21 static struct
22 {
23 	/*
24 	 * lock updates to fmt by calling __fmtlock, __fmtunlock.
25 	 * reads can start at nfmt and work backward without
26 	 * further locking. later fmtinstalls take priority over earlier
27 	 * ones because of the backwards loop.
28 	 * once installed, a format is never overwritten.
29 	 */
30 	_Atomic int	nfmt;
31 	Convfmt	fmt[Maxfmt];
32 } fmtalloc = {
33 	#ifdef PLAN9PORT
34 		ATOMIC_VAR_INIT(27),
35 	#else
36 		ATOMIC_VAR_INIT(30),
37 	#endif
38 	{
39 		{' ',	__flagfmt},
40 		{'#',	__flagfmt},
41 		{'%',	__percentfmt},
42 		{'\'',	__flagfmt},
43 		{'+',	__flagfmt},
44 		{',',	__flagfmt},
45 		{'-',	__flagfmt},
46 		{'C',	__runefmt},	/* Plan 9 addition */
47 		{'E',	__efgfmt},
48 	#ifndef PLAN9PORT
49 		{'F',	__efgfmt},	/* ANSI only */
50 	#endif
51 		{'G',	__efgfmt},
52 	#ifndef PLAN9PORT
53 		{'L',	__flagfmt},	/* ANSI only */
54 	#endif
55 		{'S',	__runesfmt},	/* Plan 9 addition */
56 		{'X',	__ifmt},
57 		{'b',	__ifmt},		/* Plan 9 addition */
58 		{'c',	__charfmt},
59 		{'d',	__ifmt},
60 		{'e',	__efgfmt},
61 		{'f',	__efgfmt},
62 		{'g',	__efgfmt},
63 		{'h',	__flagfmt},
64 	#ifndef PLAN9PORT
65 		{'i',	__ifmt},		/* ANSI only */
66 	#endif
67 		{'l',	__flagfmt},
68 		{'n',	__countfmt},
69 		{'o',	__ifmt},
70 		{'p',	__ifmt},
71 		{'r',	__errfmt},
72 		{'s',	__strfmt},
73 	#ifdef PLAN9PORT
74 		{'u',	__flagfmt},
75 	#else
76 		{'u',	__ifmt},
77 	#endif
78 		{'x',	__ifmt},
79 	}
80 };
81 
82 int	(*fmtdoquote)(int);
83 
84 /*
85  * __fmtlock() must be set
86  */
87 static int
88 __fmtinstall(int c, Fmts f)
89 {
90 	Convfmt *p;
91 	int i;
92 
93 	if(c<=0 || c>=65536)
94 		return -1;
95 	if(!f)
96 		f = __badfmt;
97 
98 	i = atomic_load(&fmtalloc.nfmt);
99 	if(i == Maxfmt)
100 		return -1;
101 	p = &fmtalloc.fmt[i];
102 	p->c = c;
103 	p->fmt = f;
104 	atomic_store(&fmtalloc.nfmt, i+1);
105 
106 	return 0;
107 }
108 
109 int
110 fmtinstall(int c, int (*f)(Fmt*))
111 {
112 	int ret;
113 
114 	__fmtlock();
115 	ret = __fmtinstall(c, f);
116 	__fmtunlock();
117 	return ret;
118 }
119 
120 static Fmts
121 fmtfmt(int c)
122 {
123 	Convfmt *p, *ep;
124 
125 	ep = &fmtalloc.fmt[atomic_load(&fmtalloc.nfmt)];
126 	for(p=ep; p-- > fmtalloc.fmt; )
127 		if(p->c == c)
128 			return p->fmt;
129 
130 	return __badfmt;
131 }
132 
133 void*
134 __fmtdispatch(Fmt *f, void *fmt, int isrunes)
135 {
136 	Rune rune, r;
137 	int i, n;
138 
139 	f->flags = 0;
140 	f->width = f->prec = 0;
141 
142 	for(;;){
143 		if(isrunes){
144 			r = *(Rune*)fmt;
145 			fmt = (Rune*)fmt + 1;
146 		}else{
147 			fmt = (char*)fmt + chartorune(&rune, (char*)fmt);
148 			r = rune;
149 		}
150 		f->r = r;
151 		switch(r){
152 		case '\0':
153 			return nil;
154 		case '.':
155 			f->flags |= FmtWidth|FmtPrec;
156 			continue;
157 		case '0':
158 			if(!(f->flags & FmtWidth)){
159 				f->flags |= FmtZero;
160 				continue;
161 			}
162 			/* fall through */
163 		case '1': case '2': case '3': case '4':
164 		case '5': case '6': case '7': case '8': case '9':
165 			i = 0;
166 			while(r >= '0' && r <= '9'){
167 				i = i * 10 + r - '0';
168 				if(isrunes){
169 					r = *(Rune*)fmt;
170 					fmt = (Rune*)fmt + 1;
171 				}else{
172 					r = *(char*)fmt;
173 					fmt = (char*)fmt + 1;
174 				}
175 			}
176 			if(isrunes)
177 				fmt = (Rune*)fmt - 1;
178 			else
179 				fmt = (char*)fmt - 1;
180 		numflag:
181 			if(f->flags & FmtWidth){
182 				f->flags |= FmtPrec;
183 				f->prec = i;
184 			}else{
185 				f->flags |= FmtWidth;
186 				f->width = i;
187 			}
188 			continue;
189 		case '*':
190 			i = va_arg(f->args, int);
191 			if(i < 0){
192 				/*
193 				 * negative precision =>
194 				 * ignore the precision.
195 				 */
196 				if(f->flags & FmtPrec){
197 					f->flags &= ~FmtPrec;
198 					f->prec = 0;
199 					continue;
200 				}
201 				i = -i;
202 				f->flags |= FmtLeft;
203 			}
204 			goto numflag;
205 		}
206 		n = (*fmtfmt(r))(f);
207 		if(n < 0)
208 			return nil;
209 		if(n == 0)
210 			return fmt;
211 	}
212 }