subr_hints.c revision 95839
1/*- 2 * Copyright (c) 2000,2001 Peter Wemm <peter@FreeBSD.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * $FreeBSD: head/sys/kern/subr_hints.c 95839 2002-05-01 02:51:50Z peter $ 27 */ 28 29#include <sys/param.h> 30#include <sys/lock.h> 31#include <sys/sx.h> 32#include <sys/systm.h> 33#include <sys/bus.h> 34 35/* 36 * Access functions for device resources. 37 */ 38 39static int checkmethod = 1; 40static int use_kenv; 41static char *hintp; 42 43/* 44 * Evil wildcarding resource string lookup. 45 * This walks the supplied env string table and returns a match. 46 * The start point can be remembered for incremental searches. 47 */ 48static int 49res_find(int *line, int *startln, 50 const char *name, int *unit, const char *resname, const char *value, 51 const char **ret_name, int *ret_namelen, int *ret_unit, 52 const char **ret_resname, int *ret_resnamelen, const char **ret_value) 53{ 54 int n = 0, hit, i = 0; 55 char r_name[32]; 56 int r_unit; 57 char r_resname[32]; 58 char r_value[128]; 59 const char *s, *cp; 60 char *p; 61 62 if (checkmethod) { 63 switch (hintmode) { 64 case 0: /* loader hints in environment only */ 65 break; 66 case 1: /* static hints only */ 67 hintp = static_hints; 68 checkmethod = 0; 69 break; 70 case 2: /* fallback mode */ 71 if (dynamic_kenv) { 72 sx_slock(&kenv_lock); 73 cp = kenvp[0]; 74 for (i = 0; cp != NULL; cp = kenvp[++i]) { 75 if (!strncmp(cp, "hint.", 5)) { 76 use_kenv = 1; 77 checkmethod = 0; 78 break; 79 } 80 } 81 sx_sunlock(&kenv_lock); 82 } else { 83 cp = kern_envp; 84 while (cp) { 85 if (strncmp(cp, "hint.", 5) == 0) { 86 cp = NULL; 87 hintp = kern_envp; 88 break; 89 } 90 while (*cp != '\0') 91 cp++; 92 cp++; 93 if (*cp == '\0') { 94 cp = NULL; 95 hintp = static_hints; 96 break; 97 } 98 } 99 } 100 break; 101 default: 102 break; 103 } 104 if (hintp == NULL) { 105 if (dynamic_kenv) { 106 use_kenv = 1; 107 checkmethod = 0; 108 } else 109 hintp = kern_envp; 110 } 111 } 112 113 if (use_kenv) { 114 sx_slock(&kenv_lock); 115 i = 0; 116 cp = kenvp[0]; 117 if (cp == NULL) { 118 sx_sunlock(&kenv_lock); 119 return (ENOENT); 120 } 121 } else 122 cp = hintp; 123 while (cp) { 124 hit = 1; 125 (*line)++; 126 if (strncmp(cp, "hint.", 5) != 0) 127 hit = 0; 128 else 129 n = sscanf(cp, "hint.%32[^.].%d.%32[^=]=%128s", 130 r_name, &r_unit, r_resname, r_value); 131 if (hit && n != 4) { 132 printf("CONFIG: invalid hint '%s'\n", cp); 133 /* XXX: abuse bogus index() declaration */ 134 p = index(cp, 'h'); 135 *p = 'H'; 136 hit = 0; 137 } 138 if (hit && startln && *startln >= 0 && *line < *startln) 139 hit = 0; 140 if (hit && name && strcmp(name, r_name) != 0) 141 hit = 0; 142 if (hit && unit && *unit != r_unit) 143 hit = 0; 144 if (hit && resname && strcmp(resname, r_resname) != 0) 145 hit = 0; 146 if (hit && value && strcmp(value, r_value) != 0) 147 hit = 0; 148 if (hit) 149 break; 150 if (use_kenv) { 151 cp = kenvp[++i]; 152 if (cp == NULL) 153 break; 154 } else { 155 while (*cp != '\0') 156 cp++; 157 cp++; 158 if (*cp == '\0') { 159 cp = NULL; 160 break; 161 } 162 } 163 } 164 if (use_kenv) 165 sx_sunlock(&kenv_lock); 166 if (cp == NULL) 167 return ENOENT; 168 169 s = cp; 170 /* This is a bit of a hack, but at least is reentrant */ 171 /* Note that it returns some !unterminated! strings. */ 172 s = index(s, '.') + 1; /* start of device */ 173 if (ret_name) 174 *ret_name = s; 175 s = index(s, '.') + 1; /* start of unit */ 176 if (ret_namelen) 177 *ret_namelen = s - *ret_name - 1; /* device length */ 178 if (ret_unit) 179 *ret_unit = r_unit; 180 s = index(s, '.') + 1; /* start of resname */ 181 if (ret_resname) 182 *ret_resname = s; 183 s = index(s, '=') + 1; /* start of value */ 184 if (ret_resnamelen) 185 *ret_resnamelen = s - *ret_resname - 1; /* value len */ 186 if (ret_value) 187 *ret_value = s; 188 if (startln) /* line number for anchor */ 189 *startln = *line + 1; 190 return 0; 191} 192 193/* 194 * Search all the data sources for matches to our query. We look for 195 * dynamic hints first as overrides for static or fallback hints. 196 */ 197static int 198resource_find(int *line, int *startln, 199 const char *name, int *unit, const char *resname, const char *value, 200 const char **ret_name, int *ret_namelen, int *ret_unit, 201 const char **ret_resname, int *ret_resnamelen, const char **ret_value) 202{ 203 int i; 204 int un; 205 206 *line = 0; 207 208 /* Search for exact unit matches first */ 209 i = res_find(line, startln, name, unit, resname, value, 210 ret_name, ret_namelen, ret_unit, ret_resname, ret_resnamelen, 211 ret_value); 212 if (i == 0) 213 return 0; 214 if (unit == NULL) 215 return ENOENT; 216 /* If we are still here, search for wildcard matches */ 217 un = -1; 218 i = res_find(line, startln, name, &un, resname, value, 219 ret_name, ret_namelen, ret_unit, ret_resname, ret_resnamelen, 220 ret_value); 221 if (i == 0) 222 return 0; 223 return ENOENT; 224} 225 226int 227resource_int_value(const char *name, int unit, const char *resname, int *result) 228{ 229 int error; 230 const char *str; 231 char *op; 232 unsigned long val; 233 int line; 234 235 line = 0; 236 error = resource_find(&line, NULL, name, &unit, resname, NULL, 237 NULL, NULL, NULL, NULL, NULL, &str); 238 if (error) 239 return error; 240 if (*str == '\0') 241 return EFTYPE; 242 val = strtoul(str, &op, 0); 243 if (*op != '\0') 244 return EFTYPE; 245 *result = val; 246 return 0; 247} 248 249int 250resource_long_value(const char *name, int unit, const char *resname, 251 long *result) 252{ 253 int error; 254 const char *str; 255 char *op; 256 unsigned long val; 257 int line; 258 259 line = 0; 260 error = resource_find(&line, NULL, name, &unit, resname, NULL, 261 NULL, NULL, NULL, NULL, NULL, &str); 262 if (error) 263 return error; 264 if (*str == '\0') 265 return EFTYPE; 266 val = strtoul(str, &op, 0); 267 if (*op != '\0') 268 return EFTYPE; 269 *result = val; 270 return 0; 271} 272 273int 274resource_string_value(const char *name, int unit, const char *resname, 275 const char **result) 276{ 277 int error; 278 const char *str; 279 int line; 280 281 line = 0; 282 error = resource_find(&line, NULL, name, &unit, resname, NULL, 283 NULL, NULL, NULL, NULL, NULL, &str); 284 if (error) 285 return error; 286 *result = str; 287 return 0; 288} 289 290/* 291 * This is a bit nasty, but allows us to not modify the env strings. 292 */ 293static const char * 294resource_string_copy(const char *s, int len) 295{ 296 static char stringbuf[256]; 297 static int offset = 0; 298 const char *ret; 299 300 if (len == 0) 301 len = strlen(s); 302 if (len > 255) 303 return NULL; 304 if ((offset + len + 1) > 255) 305 offset = 0; 306 bcopy(s, &stringbuf[offset], len); 307 stringbuf[offset + len] = '\0'; 308 ret = &stringbuf[offset]; 309 offset += len + 1; 310 return ret; 311} 312 313/* 314 * err = resource_find_at(&anchor, &name, &unit, resname, value) 315 * Iteratively fetch a list of devices wired "at" something 316 * res and value are restrictions. eg: "at", "scbus0". 317 * For practical purposes, res = required, value = optional. 318 * *name and *unit are set. 319 * set *anchor to zero before starting. 320 */ 321int 322resource_find_match(int *anchor, const char **name, int *unit, 323 const char *resname, const char *value) 324{ 325 const char *found_name; 326 int found_namelen; 327 int found_unit; 328 int ret; 329 int newln; 330 331 newln = *anchor; 332 ret = resource_find(anchor, &newln, NULL, NULL, resname, value, 333 &found_name, &found_namelen, &found_unit, NULL, NULL, NULL); 334 if (ret == 0) { 335 *name = resource_string_copy(found_name, found_namelen); 336 *unit = found_unit; 337 } 338 *anchor = newln; 339 return ret; 340} 341 342 343/* 344 * err = resource_find_dev(&anchor, name, &unit, res, value); 345 * Iterate through a list of devices, returning their unit numbers. 346 * res and value are optional restrictions. eg: "at", "scbus0". 347 * *unit is set to the value. 348 * set *anchor to zero before starting. 349 */ 350int 351resource_find_dev(int *anchor, const char *name, int *unit, 352 const char *resname, const char *value) 353{ 354 int found_unit; 355 int newln; 356 int ret; 357 358 newln = *anchor; 359 ret = resource_find(anchor, &newln, name, NULL, resname, value, 360 NULL, NULL, &found_unit, NULL, NULL, NULL); 361 if (ret == 0) { 362 *unit = found_unit; 363 } 364 *anchor = newln; 365 return ret; 366} 367