File:  [Qemu by Fabrice Bellard] / qemu / cutils.c
Revision 1.1.1.8 (vendor branch): download - view: text, annotated - select for diffs
Tue Apr 24 19:16:53 2018 UTC (3 years, 1 month ago) by root
Branches: qemu, MAIN
CVS tags: qemu1001, HEAD
qemu 1.0.1

    1: /*
    2:  * Simple C functions to supplement the C library
    3:  *
    4:  * Copyright (c) 2006 Fabrice Bellard
    5:  *
    6:  * Permission is hereby granted, free of charge, to any person obtaining a copy
    7:  * of this software and associated documentation files (the "Software"), to deal
    8:  * in the Software without restriction, including without limitation the rights
    9:  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   10:  * copies of the Software, and to permit persons to whom the Software is
   11:  * furnished to do so, subject to the following conditions:
   12:  *
   13:  * The above copyright notice and this permission notice shall be included in
   14:  * all copies or substantial portions of the Software.
   15:  *
   16:  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   17:  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   18:  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
   19:  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   20:  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   21:  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   22:  * THE SOFTWARE.
   23:  */
   24: #include "qemu-common.h"
   25: #include "host-utils.h"
   26: #include <math.h>
   27: 
   28: void pstrcpy(char *buf, int buf_size, const char *str)
   29: {
   30:     int c;
   31:     char *q = buf;
   32: 
   33:     if (buf_size <= 0)
   34:         return;
   35: 
   36:     for(;;) {
   37:         c = *str++;
   38:         if (c == 0 || q >= buf + buf_size - 1)
   39:             break;
   40:         *q++ = c;
   41:     }
   42:     *q = '\0';
   43: }
   44: 
   45: /* strcat and truncate. */
   46: char *pstrcat(char *buf, int buf_size, const char *s)
   47: {
   48:     int len;
   49:     len = strlen(buf);
   50:     if (len < buf_size)
   51:         pstrcpy(buf + len, buf_size - len, s);
   52:     return buf;
   53: }
   54: 
   55: int strstart(const char *str, const char *val, const char **ptr)
   56: {
   57:     const char *p, *q;
   58:     p = str;
   59:     q = val;
   60:     while (*q != '\0') {
   61:         if (*p != *q)
   62:             return 0;
   63:         p++;
   64:         q++;
   65:     }
   66:     if (ptr)
   67:         *ptr = p;
   68:     return 1;
   69: }
   70: 
   71: int stristart(const char *str, const char *val, const char **ptr)
   72: {
   73:     const char *p, *q;
   74:     p = str;
   75:     q = val;
   76:     while (*q != '\0') {
   77:         if (qemu_toupper(*p) != qemu_toupper(*q))
   78:             return 0;
   79:         p++;
   80:         q++;
   81:     }
   82:     if (ptr)
   83:         *ptr = p;
   84:     return 1;
   85: }
   86: 
   87: /* XXX: use host strnlen if available ? */
   88: int qemu_strnlen(const char *s, int max_len)
   89: {
   90:     int i;
   91: 
   92:     for(i = 0; i < max_len; i++) {
   93:         if (s[i] == '\0') {
   94:             break;
   95:         }
   96:     }
   97:     return i;
   98: }
   99: 
  100: time_t mktimegm(struct tm *tm)
  101: {
  102:     time_t t;
  103:     int y = tm->tm_year + 1900, m = tm->tm_mon + 1, d = tm->tm_mday;
  104:     if (m < 3) {
  105:         m += 12;
  106:         y--;
  107:     }
  108:     t = 86400 * (d + (153 * m - 457) / 5 + 365 * y + y / 4 - y / 100 + 
  109:                  y / 400 - 719469);
  110:     t += 3600 * tm->tm_hour + 60 * tm->tm_min + tm->tm_sec;
  111:     return t;
  112: }
  113: 
  114: int qemu_fls(int i)
  115: {
  116:     return 32 - clz32(i);
  117: }
  118: 
  119: /*
  120:  * Make sure data goes on disk, but if possible do not bother to
  121:  * write out the inode just for timestamp updates.
  122:  *
  123:  * Unfortunately even in 2009 many operating systems do not support
  124:  * fdatasync and have to fall back to fsync.
  125:  */
  126: int qemu_fdatasync(int fd)
  127: {
  128: #ifdef CONFIG_FDATASYNC
  129:     return fdatasync(fd);
  130: #else
  131:     return fsync(fd);
  132: #endif
  133: }
  134: 
  135: /* io vectors */
  136: 
  137: void qemu_iovec_init(QEMUIOVector *qiov, int alloc_hint)
  138: {
  139:     qiov->iov = g_malloc(alloc_hint * sizeof(struct iovec));
  140:     qiov->niov = 0;
  141:     qiov->nalloc = alloc_hint;
  142:     qiov->size = 0;
  143: }
  144: 
  145: void qemu_iovec_init_external(QEMUIOVector *qiov, struct iovec *iov, int niov)
  146: {
  147:     int i;
  148: 
  149:     qiov->iov = iov;
  150:     qiov->niov = niov;
  151:     qiov->nalloc = -1;
  152:     qiov->size = 0;
  153:     for (i = 0; i < niov; i++)
  154:         qiov->size += iov[i].iov_len;
  155: }
  156: 
  157: void qemu_iovec_add(QEMUIOVector *qiov, void *base, size_t len)
  158: {
  159:     assert(qiov->nalloc != -1);
  160: 
  161:     if (qiov->niov == qiov->nalloc) {
  162:         qiov->nalloc = 2 * qiov->nalloc + 1;
  163:         qiov->iov = g_realloc(qiov->iov, qiov->nalloc * sizeof(struct iovec));
  164:     }
  165:     qiov->iov[qiov->niov].iov_base = base;
  166:     qiov->iov[qiov->niov].iov_len = len;
  167:     qiov->size += len;
  168:     ++qiov->niov;
  169: }
  170: 
  171: /*
  172:  * Copies iovecs from src to the end of dst. It starts copying after skipping
  173:  * the given number of bytes in src and copies until src is completely copied
  174:  * or the total size of the copied iovec reaches size.The size of the last
  175:  * copied iovec is changed in order to fit the specified total size if it isn't
  176:  * a perfect fit already.
  177:  */
  178: void qemu_iovec_copy(QEMUIOVector *dst, QEMUIOVector *src, uint64_t skip,
  179:     size_t size)
  180: {
  181:     int i;
  182:     size_t done;
  183:     void *iov_base;
  184:     uint64_t iov_len;
  185: 
  186:     assert(dst->nalloc != -1);
  187: 
  188:     done = 0;
  189:     for (i = 0; (i < src->niov) && (done != size); i++) {
  190:         if (skip >= src->iov[i].iov_len) {
  191:             /* Skip the whole iov */
  192:             skip -= src->iov[i].iov_len;
  193:             continue;
  194:         } else {
  195:             /* Skip only part (or nothing) of the iov */
  196:             iov_base = (uint8_t*) src->iov[i].iov_base + skip;
  197:             iov_len = src->iov[i].iov_len - skip;
  198:             skip = 0;
  199:         }
  200: 
  201:         if (done + iov_len > size) {
  202:             qemu_iovec_add(dst, iov_base, size - done);
  203:             break;
  204:         } else {
  205:             qemu_iovec_add(dst, iov_base, iov_len);
  206:         }
  207:         done += iov_len;
  208:     }
  209: }
  210: 
  211: void qemu_iovec_concat(QEMUIOVector *dst, QEMUIOVector *src, size_t size)
  212: {
  213:     qemu_iovec_copy(dst, src, 0, size);
  214: }
  215: 
  216: void qemu_iovec_destroy(QEMUIOVector *qiov)
  217: {
  218:     assert(qiov->nalloc != -1);
  219: 
  220:     qemu_iovec_reset(qiov);
  221:     g_free(qiov->iov);
  222:     qiov->nalloc = 0;
  223:     qiov->iov = NULL;
  224: }
  225: 
  226: void qemu_iovec_reset(QEMUIOVector *qiov)
  227: {
  228:     assert(qiov->nalloc != -1);
  229: 
  230:     qiov->niov = 0;
  231:     qiov->size = 0;
  232: }
  233: 
  234: void qemu_iovec_to_buffer(QEMUIOVector *qiov, void *buf)
  235: {
  236:     uint8_t *p = (uint8_t *)buf;
  237:     int i;
  238: 
  239:     for (i = 0; i < qiov->niov; ++i) {
  240:         memcpy(p, qiov->iov[i].iov_base, qiov->iov[i].iov_len);
  241:         p += qiov->iov[i].iov_len;
  242:     }
  243: }
  244: 
  245: void qemu_iovec_from_buffer(QEMUIOVector *qiov, const void *buf, size_t count)
  246: {
  247:     const uint8_t *p = (const uint8_t *)buf;
  248:     size_t copy;
  249:     int i;
  250: 
  251:     for (i = 0; i < qiov->niov && count; ++i) {
  252:         copy = count;
  253:         if (copy > qiov->iov[i].iov_len)
  254:             copy = qiov->iov[i].iov_len;
  255:         memcpy(qiov->iov[i].iov_base, p, copy);
  256:         p     += copy;
  257:         count -= copy;
  258:     }
  259: }
  260: 
  261: void qemu_iovec_memset(QEMUIOVector *qiov, int c, size_t count)
  262: {
  263:     size_t n;
  264:     int i;
  265: 
  266:     for (i = 0; i < qiov->niov && count; ++i) {
  267:         n = MIN(count, qiov->iov[i].iov_len);
  268:         memset(qiov->iov[i].iov_base, c, n);
  269:         count -= n;
  270:     }
  271: }
  272: 
  273: void qemu_iovec_memset_skip(QEMUIOVector *qiov, int c, size_t count,
  274:                             size_t skip)
  275: {
  276:     int i;
  277:     size_t done;
  278:     void *iov_base;
  279:     uint64_t iov_len;
  280: 
  281:     done = 0;
  282:     for (i = 0; (i < qiov->niov) && (done != count); i++) {
  283:         if (skip >= qiov->iov[i].iov_len) {
  284:             /* Skip the whole iov */
  285:             skip -= qiov->iov[i].iov_len;
  286:             continue;
  287:         } else {
  288:             /* Skip only part (or nothing) of the iov */
  289:             iov_base = (uint8_t*) qiov->iov[i].iov_base + skip;
  290:             iov_len = qiov->iov[i].iov_len - skip;
  291:             skip = 0;
  292:         }
  293: 
  294:         if (done + iov_len > count) {
  295:             memset(iov_base, c, count - done);
  296:             break;
  297:         } else {
  298:             memset(iov_base, c, iov_len);
  299:         }
  300:         done += iov_len;
  301:     }
  302: }
  303: 
  304: #ifndef _WIN32
  305: /* Sets a specific flag */
  306: int fcntl_setfl(int fd, int flag)
  307: {
  308:     int flags;
  309: 
  310:     flags = fcntl(fd, F_GETFL);
  311:     if (flags == -1)
  312:         return -errno;
  313: 
  314:     if (fcntl(fd, F_SETFL, flags | flag) == -1)
  315:         return -errno;
  316: 
  317:     return 0;
  318: }
  319: #endif
  320: 
  321: static int64_t suffix_mul(char suffix, int64_t unit)
  322: {
  323:     switch (qemu_toupper(suffix)) {
  324:     case STRTOSZ_DEFSUFFIX_B:
  325:         return 1;
  326:     case STRTOSZ_DEFSUFFIX_KB:
  327:         return unit;
  328:     case STRTOSZ_DEFSUFFIX_MB:
  329:         return unit * unit;
  330:     case STRTOSZ_DEFSUFFIX_GB:
  331:         return unit * unit * unit;
  332:     case STRTOSZ_DEFSUFFIX_TB:
  333:         return unit * unit * unit * unit;
  334:     }
  335:     return -1;
  336: }
  337: 
  338: /*
  339:  * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
  340:  * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
  341:  * in *end, if not NULL. Return -1 on error.
  342:  */
  343: int64_t strtosz_suffix_unit(const char *nptr, char **end,
  344:                             const char default_suffix, int64_t unit)
  345: {
  346:     int64_t retval = -1;
  347:     char *endptr;
  348:     unsigned char c;
  349:     int mul_required = 0;
  350:     double val, mul, integral, fraction;
  351: 
  352:     errno = 0;
  353:     val = strtod(nptr, &endptr);
  354:     if (isnan(val) || endptr == nptr || errno != 0) {
  355:         goto fail;
  356:     }
  357:     fraction = modf(val, &integral);
  358:     if (fraction != 0) {
  359:         mul_required = 1;
  360:     }
  361:     c = *endptr;
  362:     mul = suffix_mul(c, unit);
  363:     if (mul >= 0) {
  364:         endptr++;
  365:     } else {
  366:         mul = suffix_mul(default_suffix, unit);
  367:         assert(mul >= 0);
  368:     }
  369:     if (mul == 1 && mul_required) {
  370:         goto fail;
  371:     }
  372:     if ((val * mul >= INT64_MAX) || val < 0) {
  373:         goto fail;
  374:     }
  375:     retval = val * mul;
  376: 
  377: fail:
  378:     if (end) {
  379:         *end = endptr;
  380:     }
  381: 
  382:     return retval;
  383: }
  384: 
  385: int64_t strtosz_suffix(const char *nptr, char **end, const char default_suffix)
  386: {
  387:     return strtosz_suffix_unit(nptr, end, default_suffix, 1024);
  388: }
  389: 
  390: int64_t strtosz(const char *nptr, char **end)
  391: {
  392:     return strtosz_suffix(nptr, end, STRTOSZ_DEFSUFFIX_MB);
  393: }
  394: 
  395: int qemu_parse_fd(const char *param)
  396: {
  397:     int fd;
  398:     char *endptr = NULL;
  399: 
  400:     fd = strtol(param, &endptr, 10);
  401:     if (*endptr || (fd == 0 && param == endptr)) {
  402:         return -1;
  403:     }
  404:     return fd;
  405: }

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