1 85231fd8 2006-05-21 devnull /* Copyright (c) 2002-2006 Lucent Technologies; see LICENSE */
  2 91c13e54 2004-02-29 devnull #include <stdarg.h>
  3 91c13e54 2004-02-29 devnull #include <string.h>
  4 c3c9c7b6 2020-05-08 rsc 
  5 c3c9c7b6 2020-05-08 rsc /*
  6 c3c9c7b6 2020-05-08 rsc  * As of 2020, older systems like RHEL 6 and AIX still do not have C11 atomics.
  7 c3c9c7b6 2020-05-08 rsc  * On those systems, make the code use volatile int accesses and hope for the best.
  8 c3c9c7b6 2020-05-08 rsc  * (Most uses of fmtinstall are not actually racing with calls to print that lookup
  9 c3c9c7b6 2020-05-08 rsc  * formats. The code used volatile here for years without too many problems,
 10 c3c9c7b6 2020-05-08 rsc  * even though that's technically racy. A mutex is not OK, because we want to
 11 c3c9c7b6 2020-05-08 rsc  * be able to call print from signal handlers.)
 12 c3c9c7b6 2020-05-08 rsc  *
 13 bd6f1206 2020-05-08 crossd  * RHEL is using an old GCC (atomics were added in GCC 4.9).
 14 c3c9c7b6 2020-05-08 rsc  * AIX is using its own IBM compiler (XL C).
 15 c3c9c7b6 2020-05-08 rsc  */
 16 bd6f1206 2020-05-08 crossd #if __IBMC__ || !__clang__ && __GNUC__ && (__GNUC__ < 4 || (__GNUC__==4 && __GNUC_MINOR__<9))
 17 c3c9c7b6 2020-05-08 rsc #warning not using C11 stdatomic on legacy system
 18 c3c9c7b6 2020-05-08 rsc #define _Atomic volatile
 19 c3c9c7b6 2020-05-08 rsc #define atomic_load(x) (*(x))
 20 c3c9c7b6 2020-05-08 rsc #define atomic_store(x, y) (*(x)=(y))
 21 c3c9c7b6 2020-05-08 rsc #define ATOMIC_VAR_INIT(x) (x)
 22 c3c9c7b6 2020-05-08 rsc #else
 23 9505cd15 2020-01-14 rsc #include <stdatomic.h>
 24 c3c9c7b6 2020-05-08 rsc #endif
 25 c3c9c7b6 2020-05-08 rsc 
 26 e5aa96ac 2004-12-26 devnull #include "plan9.h"
 27 91c13e54 2004-02-29 devnull #include "fmt.h"
 28 91c13e54 2004-02-29 devnull #include "fmtdef.h"
 29 91c13e54 2004-02-29 devnull 
 30 91c13e54 2004-02-29 devnull enum
 31 91c13e54 2004-02-29 devnull {
 32 9505cd15 2020-01-14 rsc 	Maxfmt = 128
 33 91c13e54 2004-02-29 devnull };
 34 91c13e54 2004-02-29 devnull 
 35 91c13e54 2004-02-29 devnull typedef struct Convfmt Convfmt;
 36 91c13e54 2004-02-29 devnull struct Convfmt
 37 91c13e54 2004-02-29 devnull {
 38 91c13e54 2004-02-29 devnull 	int	c;
 39 9505cd15 2020-01-14 rsc 	Fmts	fmt;
 40 91c13e54 2004-02-29 devnull };
 41 91c13e54 2004-02-29 devnull 
 42 85231fd8 2006-05-21 devnull static struct
 43 91c13e54 2004-02-29 devnull {
 44 9505cd15 2020-01-14 rsc 	/*
 45 9505cd15 2020-01-14 rsc 	 * lock updates to fmt by calling __fmtlock, __fmtunlock.
 46 9505cd15 2020-01-14 rsc 	 * reads can start at nfmt and work backward without
 47 9505cd15 2020-01-14 rsc 	 * further locking. later fmtinstalls take priority over earlier
 48 9505cd15 2020-01-14 rsc 	 * ones because of the backwards loop.
 49 9505cd15 2020-01-14 rsc 	 * once installed, a format is never overwritten.
 50 9505cd15 2020-01-14 rsc 	 */
 51 9505cd15 2020-01-14 rsc 	_Atomic int	nfmt;
 52 91c13e54 2004-02-29 devnull 	Convfmt	fmt[Maxfmt];
 53 9505cd15 2020-01-14 rsc } fmtalloc = {
 54 9505cd15 2020-01-14 rsc 	#ifdef PLAN9PORT
 55 9505cd15 2020-01-14 rsc 		ATOMIC_VAR_INIT(27),
 56 9505cd15 2020-01-14 rsc 	#else
 57 9505cd15 2020-01-14 rsc 		ATOMIC_VAR_INIT(30),
 58 9505cd15 2020-01-14 rsc 	#endif
 59 9505cd15 2020-01-14 rsc 	{
 60 9505cd15 2020-01-14 rsc 		{' ',	__flagfmt},
 61 9505cd15 2020-01-14 rsc 		{'#',	__flagfmt},
 62 9505cd15 2020-01-14 rsc 		{'%',	__percentfmt},
 63 9505cd15 2020-01-14 rsc 		{'\'',	__flagfmt},
 64 9505cd15 2020-01-14 rsc 		{'+',	__flagfmt},
 65 9505cd15 2020-01-14 rsc 		{',',	__flagfmt},
 66 9505cd15 2020-01-14 rsc 		{'-',	__flagfmt},
 67 9505cd15 2020-01-14 rsc 		{'C',	__runefmt},	/* Plan 9 addition */
 68 9505cd15 2020-01-14 rsc 		{'E',	__efgfmt},
 69 9505cd15 2020-01-14 rsc 	#ifndef PLAN9PORT
 70 9505cd15 2020-01-14 rsc 		{'F',	__efgfmt},	/* ANSI only */
 71 9505cd15 2020-01-14 rsc 	#endif
 72 9505cd15 2020-01-14 rsc 		{'G',	__efgfmt},
 73 9505cd15 2020-01-14 rsc 	#ifndef PLAN9PORT
 74 9505cd15 2020-01-14 rsc 		{'L',	__flagfmt},	/* ANSI only */
 75 9505cd15 2020-01-14 rsc 	#endif
 76 9505cd15 2020-01-14 rsc 		{'S',	__runesfmt},	/* Plan 9 addition */
 77 9505cd15 2020-01-14 rsc 		{'X',	__ifmt},
 78 9505cd15 2020-01-14 rsc 		{'b',	__ifmt},		/* Plan 9 addition */
 79 9505cd15 2020-01-14 rsc 		{'c',	__charfmt},
 80 9505cd15 2020-01-14 rsc 		{'d',	__ifmt},
 81 9505cd15 2020-01-14 rsc 		{'e',	__efgfmt},
 82 9505cd15 2020-01-14 rsc 		{'f',	__efgfmt},
 83 9505cd15 2020-01-14 rsc 		{'g',	__efgfmt},
 84 9505cd15 2020-01-14 rsc 		{'h',	__flagfmt},
 85 9505cd15 2020-01-14 rsc 	#ifndef PLAN9PORT
 86 9505cd15 2020-01-14 rsc 		{'i',	__ifmt},		/* ANSI only */
 87 9505cd15 2020-01-14 rsc 	#endif
 88 9505cd15 2020-01-14 rsc 		{'l',	__flagfmt},
 89 9505cd15 2020-01-14 rsc 		{'n',	__countfmt},
 90 9505cd15 2020-01-14 rsc 		{'o',	__ifmt},
 91 9505cd15 2020-01-14 rsc 		{'p',	__ifmt},
 92 9505cd15 2020-01-14 rsc 		{'r',	__errfmt},
 93 9505cd15 2020-01-14 rsc 		{'s',	__strfmt},
 94 9505cd15 2020-01-14 rsc 	#ifdef PLAN9PORT
 95 9505cd15 2020-01-14 rsc 		{'u',	__flagfmt},
 96 9505cd15 2020-01-14 rsc 	#else
 97 9505cd15 2020-01-14 rsc 		{'u',	__ifmt},
 98 9505cd15 2020-01-14 rsc 	#endif
 99 9505cd15 2020-01-14 rsc 		{'x',	__ifmt},
100 9505cd15 2020-01-14 rsc 	}
101 91c13e54 2004-02-29 devnull };
102 91c13e54 2004-02-29 devnull 
103 91c13e54 2004-02-29 devnull int	(*fmtdoquote)(int);
104 91c13e54 2004-02-29 devnull 
105 91c13e54 2004-02-29 devnull /*
106 9505cd15 2020-01-14 rsc  * __fmtlock() must be set
107 91c13e54 2004-02-29 devnull  */
108 91c13e54 2004-02-29 devnull static int
109 91c13e54 2004-02-29 devnull __fmtinstall(int c, Fmts f)
110 91c13e54 2004-02-29 devnull {
111 9505cd15 2020-01-14 rsc 	Convfmt *p;
112 9505cd15 2020-01-14 rsc 	int i;
113 91c13e54 2004-02-29 devnull 
114 91c13e54 2004-02-29 devnull 	if(c<=0 || c>=65536)
115 91c13e54 2004-02-29 devnull 		return -1;
116 91c13e54 2004-02-29 devnull 	if(!f)
117 91c13e54 2004-02-29 devnull 		f = __badfmt;
118 91c13e54 2004-02-29 devnull 
119 9505cd15 2020-01-14 rsc 	i = atomic_load(&fmtalloc.nfmt);
120 9505cd15 2020-01-14 rsc 	if(i == Maxfmt)
121 91c13e54 2004-02-29 devnull 		return -1;
122 9505cd15 2020-01-14 rsc 	p = &fmtalloc.fmt[i];
123 9505cd15 2020-01-14 rsc 	p->c = c;
124 91c13e54 2004-02-29 devnull 	p->fmt = f;
125 9505cd15 2020-01-14 rsc 	atomic_store(&fmtalloc.nfmt, i+1);
126 91c13e54 2004-02-29 devnull 
127 91c13e54 2004-02-29 devnull 	return 0;
128 91c13e54 2004-02-29 devnull }
129 91c13e54 2004-02-29 devnull 
130 91c13e54 2004-02-29 devnull int
131 e5aa96ac 2004-12-26 devnull fmtinstall(int c, int (*f)(Fmt*))
132 91c13e54 2004-02-29 devnull {
133 91c13e54 2004-02-29 devnull 	int ret;
134 91c13e54 2004-02-29 devnull 
135 9505cd15 2020-01-14 rsc 	__fmtlock();
136 91c13e54 2004-02-29 devnull 	ret = __fmtinstall(c, f);
137 9505cd15 2020-01-14 rsc 	__fmtunlock();
138 91c13e54 2004-02-29 devnull 	return ret;
139 91c13e54 2004-02-29 devnull }
140 91c13e54 2004-02-29 devnull 
141 91c13e54 2004-02-29 devnull static Fmts
142 91c13e54 2004-02-29 devnull fmtfmt(int c)
143 91c13e54 2004-02-29 devnull {
144 9505cd15 2020-01-14 rsc 	Convfmt *p, *ep;
145 91c13e54 2004-02-29 devnull 
146 9505cd15 2020-01-14 rsc 	ep = &fmtalloc.fmt[atomic_load(&fmtalloc.nfmt)];
147 9505cd15 2020-01-14 rsc 	for(p=ep; p-- > fmtalloc.fmt; )
148 9505cd15 2020-01-14 rsc 		if(p->c == c)
149 91c13e54 2004-02-29 devnull 			return p->fmt;
150 91c13e54 2004-02-29 devnull 
151 91c13e54 2004-02-29 devnull 	return __badfmt;
152 91c13e54 2004-02-29 devnull }
153 91c13e54 2004-02-29 devnull 
154 91c13e54 2004-02-29 devnull void*
155 91c13e54 2004-02-29 devnull __fmtdispatch(Fmt *f, void *fmt, int isrunes)
156 91c13e54 2004-02-29 devnull {
157 91c13e54 2004-02-29 devnull 	Rune rune, r;
158 91c13e54 2004-02-29 devnull 	int i, n;
159 91c13e54 2004-02-29 devnull 
160 91c13e54 2004-02-29 devnull 	f->flags = 0;
161 91c13e54 2004-02-29 devnull 	f->width = f->prec = 0;
162 91c13e54 2004-02-29 devnull 
163 91c13e54 2004-02-29 devnull 	for(;;){
164 91c13e54 2004-02-29 devnull 		if(isrunes){
165 91c13e54 2004-02-29 devnull 			r = *(Rune*)fmt;
166 91c13e54 2004-02-29 devnull 			fmt = (Rune*)fmt + 1;
167 91c13e54 2004-02-29 devnull 		}else{
168 91c13e54 2004-02-29 devnull 			fmt = (char*)fmt + chartorune(&rune, (char*)fmt);
169 91c13e54 2004-02-29 devnull 			r = rune;
170 91c13e54 2004-02-29 devnull 		}
171 91c13e54 2004-02-29 devnull 		f->r = r;
172 91c13e54 2004-02-29 devnull 		switch(r){
173 91c13e54 2004-02-29 devnull 		case '\0':
174 91c13e54 2004-02-29 devnull 			return nil;
175 91c13e54 2004-02-29 devnull 		case '.':
176 91c13e54 2004-02-29 devnull 			f->flags |= FmtWidth|FmtPrec;
177 91c13e54 2004-02-29 devnull 			continue;
178 91c13e54 2004-02-29 devnull 		case '0':
179 91c13e54 2004-02-29 devnull 			if(!(f->flags & FmtWidth)){
180 91c13e54 2004-02-29 devnull 				f->flags |= FmtZero;
181 91c13e54 2004-02-29 devnull 				continue;
182 91c13e54 2004-02-29 devnull 			}
183 91c13e54 2004-02-29 devnull 			/* fall through */
184 91c13e54 2004-02-29 devnull 		case '1': case '2': case '3': case '4':
185 91c13e54 2004-02-29 devnull 		case '5': case '6': case '7': case '8': case '9':
186 91c13e54 2004-02-29 devnull 			i = 0;
187 91c13e54 2004-02-29 devnull 			while(r >= '0' && r <= '9'){
188 91c13e54 2004-02-29 devnull 				i = i * 10 + r - '0';
189 91c13e54 2004-02-29 devnull 				if(isrunes){
190 91c13e54 2004-02-29 devnull 					r = *(Rune*)fmt;
191 91c13e54 2004-02-29 devnull 					fmt = (Rune*)fmt + 1;
192 91c13e54 2004-02-29 devnull 				}else{
193 91c13e54 2004-02-29 devnull 					r = *(char*)fmt;
194 91c13e54 2004-02-29 devnull 					fmt = (char*)fmt + 1;
195 91c13e54 2004-02-29 devnull 				}
196 91c13e54 2004-02-29 devnull 			}
197 91c13e54 2004-02-29 devnull 			if(isrunes)
198 91c13e54 2004-02-29 devnull 				fmt = (Rune*)fmt - 1;
199 91c13e54 2004-02-29 devnull 			else
200 91c13e54 2004-02-29 devnull 				fmt = (char*)fmt - 1;
201 91c13e54 2004-02-29 devnull 		numflag:
202 91c13e54 2004-02-29 devnull 			if(f->flags & FmtWidth){
203 91c13e54 2004-02-29 devnull 				f->flags |= FmtPrec;
204 91c13e54 2004-02-29 devnull 				f->prec = i;
205 91c13e54 2004-02-29 devnull 			}else{
206 91c13e54 2004-02-29 devnull 				f->flags |= FmtWidth;
207 91c13e54 2004-02-29 devnull 				f->width = i;
208 91c13e54 2004-02-29 devnull 			}
209 91c13e54 2004-02-29 devnull 			continue;
210 91c13e54 2004-02-29 devnull 		case '*':
211 91c13e54 2004-02-29 devnull 			i = va_arg(f->args, int);
212 91c13e54 2004-02-29 devnull 			if(i < 0){
213 91c13e54 2004-02-29 devnull 				/*
214 91c13e54 2004-02-29 devnull 				 * negative precision =>
215 91c13e54 2004-02-29 devnull 				 * ignore the precision.
216 91c13e54 2004-02-29 devnull 				 */
217 91c13e54 2004-02-29 devnull 				if(f->flags & FmtPrec){
218 91c13e54 2004-02-29 devnull 					f->flags &= ~FmtPrec;
219 91c13e54 2004-02-29 devnull 					f->prec = 0;
220 91c13e54 2004-02-29 devnull 					continue;
221 91c13e54 2004-02-29 devnull 				}
222 91c13e54 2004-02-29 devnull 				i = -i;
223 91c13e54 2004-02-29 devnull 				f->flags |= FmtLeft;
224 91c13e54 2004-02-29 devnull 			}
225 91c13e54 2004-02-29 devnull 			goto numflag;
226 91c13e54 2004-02-29 devnull 		}
227 91c13e54 2004-02-29 devnull 		n = (*fmtfmt(r))(f);
228 91c13e54 2004-02-29 devnull 		if(n < 0)
229 91c13e54 2004-02-29 devnull 			return nil;
230 91c13e54 2004-02-29 devnull 		if(n == 0)
231 91c13e54 2004-02-29 devnull 			return fmt;
232 91c13e54 2004-02-29 devnull 	}
233 91c13e54 2004-02-29 devnull }