diff options
Diffstat (limited to 'src/third_party/unwind/dist/src/os-linux.h')
-rw-r--r-- | src/third_party/unwind/dist/src/os-linux.h | 297 |
1 files changed, 297 insertions, 0 deletions
diff --git a/src/third_party/unwind/dist/src/os-linux.h b/src/third_party/unwind/dist/src/os-linux.h new file mode 100644 index 00000000000..3976b38cc29 --- /dev/null +++ b/src/third_party/unwind/dist/src/os-linux.h @@ -0,0 +1,297 @@ +/* libunwind - a platform-independent unwind library + Copyright (C) 2003-2004 Hewlett-Packard Co + Copyright (C) 2007 David Mosberger-Tang + Contributed by David Mosberger-Tang <dmosberger@gmail.com> + +This file is part of libunwind. + +Permission is hereby granted, free of charge, to any person obtaining +a copy of this software and associated documentation files (the +"Software"), to deal in the Software without restriction, including +without limitation the rights to use, copy, modify, merge, publish, +distribute, sublicense, and/or sell copies of the Software, and to +permit persons to whom the Software is furnished to do so, subject to +the following conditions: + +The above copyright notice and this permission notice shall be +included in all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, +EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND +NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE +LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION +OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION +WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ + +#ifndef os_linux_h +#define os_linux_h + +struct map_iterator + { + off_t offset; + int fd; + size_t buf_size; + char *buf; + char *buf_end; + char *path; + }; + +static inline char * +ltoa (char *buf, long val) +{ + char *cp = buf, tmp; + ssize_t i, len; + + do + { + *cp++ = '0' + (val % 10); + val /= 10; + } + while (val); + + /* reverse the order of the digits: */ + len = cp - buf; + --cp; + for (i = 0; i < len / 2; ++i) + { + tmp = buf[i]; + buf[i] = cp[-i]; + cp[-i] = tmp; + } + return buf + len; +} + +static inline int +maps_init (struct map_iterator *mi, pid_t pid) +{ + char path[sizeof ("/proc/0123456789/maps")], *cp; + + memcpy (path, "/proc/", 6); + cp = ltoa (path + 6, pid); + assert (cp + 6 < path + sizeof (path)); + memcpy (cp, "/maps", 6); + + mi->fd = open (path, O_RDONLY); + if (mi->fd >= 0) + { + /* Try to allocate a page-sized buffer. */ + mi->buf_size = getpagesize (); + cp = mmap (NULL, mi->buf_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (cp == MAP_FAILED) + { + close(mi->fd); + mi->fd = -1; + return -1; + } + else + { + mi->offset = 0; + mi->buf = mi->buf_end = cp + mi->buf_size; + return 0; + } + } + return -1; +} + +static inline char * +skip_whitespace (char *cp) +{ + if (!cp) + return NULL; + + while (*cp == ' ' || *cp == '\t') + ++cp; + return cp; +} + +static inline char * +scan_hex (char *cp, unsigned long *valp) +{ + unsigned long num_digits = 0, digit, val = 0; + + cp = skip_whitespace (cp); + if (!cp) + return NULL; + + while (1) + { + digit = *cp; + if ((digit - '0') <= 9) + digit -= '0'; + else if ((digit - 'a') < 6) + digit -= 'a' - 10; + else if ((digit - 'A') < 6) + digit -= 'A' - 10; + else + break; + val = (val << 4) | digit; + ++num_digits; + ++cp; + } + if (!num_digits) + return NULL; + *valp = val; + return cp; +} + +static inline char * +scan_dec (char *cp, unsigned long *valp) +{ + unsigned long num_digits = 0, digit, val = 0; + + if (!(cp = skip_whitespace (cp))) + return NULL; + + while (1) + { + digit = *cp; + if ((digit - '0') <= 9) + { + digit -= '0'; + ++cp; + } + else + break; + val = (10 * val) + digit; + ++num_digits; + } + if (!num_digits) + return NULL; + *valp = val; + return cp; +} + +static inline char * +scan_char (char *cp, char *valp) +{ + if (!cp) + return NULL; + + *valp = *cp; + + /* don't step over NUL terminator */ + if (*cp) + ++cp; + return cp; +} + +/* Scan a string delimited by white-space. Fails on empty string or + if string is doesn't fit in the specified buffer. */ +static inline char * +scan_string (char *cp, char *valp, size_t buf_size) +{ + size_t i = 0; + + if (!(cp = skip_whitespace (cp))) + return NULL; + + while (*cp != ' ' && *cp != '\t' && *cp != '\0') + { + if ((valp != NULL) && (i < buf_size - 1)) + valp[i++] = *cp; + ++cp; + } + if (i == 0 || i >= buf_size) + return NULL; + valp[i] = '\0'; + return cp; +} + +static inline int +maps_next (struct map_iterator *mi, + unsigned long *low, unsigned long *high, unsigned long *offset) +{ + char perm[16], dash = 0, colon = 0, *cp; + unsigned long major, minor, inum; + ssize_t i, nread; + + if (mi->fd < 0) + return 0; + + while (1) + { + ssize_t bytes_left = mi->buf_end - mi->buf; + char *eol = NULL; + + for (i = 0; i < bytes_left; ++i) + { + if (mi->buf[i] == '\n') + { + eol = mi->buf + i; + break; + } + else if (mi->buf[i] == '\0') + break; + } + if (!eol) + { + /* copy down the remaining bytes, if any */ + if (bytes_left > 0) + memmove (mi->buf_end - mi->buf_size, mi->buf, bytes_left); + + mi->buf = mi->buf_end - mi->buf_size; + nread = read (mi->fd, mi->buf + bytes_left, + mi->buf_size - bytes_left); + if (nread <= 0) + return 0; + else if ((size_t) (nread + bytes_left) < mi->buf_size) + { + /* Move contents to the end of the buffer so we + maintain the invariant that all bytes between + mi->buf and mi->buf_end are valid. */ + memmove (mi->buf_end - nread - bytes_left, mi->buf, + nread + bytes_left); + mi->buf = mi->buf_end - nread - bytes_left; + } + + eol = mi->buf + bytes_left + nread - 1; + + for (i = bytes_left; i < bytes_left + nread; ++i) + if (mi->buf[i] == '\n') + { + eol = mi->buf + i; + break; + } + } + cp = mi->buf; + mi->buf = eol + 1; + *eol = '\0'; + + /* scan: "LOW-HIGH PERM OFFSET MAJOR:MINOR INUM PATH" */ + cp = scan_hex (cp, low); + cp = scan_char (cp, &dash); + cp = scan_hex (cp, high); + cp = scan_string (cp, perm, sizeof (perm)); + cp = scan_hex (cp, offset); + cp = scan_hex (cp, &major); + cp = scan_char (cp, &colon); + cp = scan_hex (cp, &minor); + cp = scan_dec (cp, &inum); + cp = mi->path = skip_whitespace (cp); + if (!cp) + continue; + cp = scan_string (cp, NULL, 0); + if (dash != '-' || colon != ':') + continue; /* skip line with unknown or bad format */ + return 1; + } + return 0; +} + +static inline void +maps_close (struct map_iterator *mi) +{ + if (mi->fd < 0) + return; + close (mi->fd); + mi->fd = -1; + if (mi->buf) + { + munmap (mi->buf_end - mi->buf_size, mi->buf_size); + mi->buf = mi->buf_end = NULL; + } +} + +#endif /* os_linux_h */ |