X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=src%2Frrd_open.c;h=6e8a042544be2891bc7500eff036b90e96868e92;hb=5df1338292439550fd027edf90489f62cfdedba2;hp=e18209175e7ea8e5f63d800e3047a269c940a8d1;hpb=7f30ee2ae089520606cbb7e38fab9981618771f5;p=rrdtool.git diff --git a/src/rrd_open.c b/src/rrd_open.c index e182091..6e8a042 100644 --- a/src/rrd_open.c +++ b/src/rrd_open.c @@ -73,11 +73,14 @@ //#define ONE_PAGE 1 /* Avoid calling madvise on areas that were already hinted. May be benefical if * your syscalls are very slow */ -//#define CHECK_MADVISE_OVERLAPS 1 +#define CHECK_MADVISE_OVERLAPS 1 #ifdef HAVE_MMAP +/* the cast to void* is there to avoid this warning seen on ia64 with certain + versions of gcc: 'cast increases required alignment of target type' +*/ #define __rrd_read(dst, dst_t, cnt) \ - (dst) = (dst_t*) (data + offset); \ + (dst) = (dst_t*)(void*) (data + offset); \ offset += sizeof(dst_t) * (cnt) #else #define __rrd_read(dst, dst_t, cnt) \ @@ -140,7 +143,12 @@ rrd_file_t *rrd_open( off_t offset = 0; struct stat statb; rrd_file_t *rrd_file = NULL; + off_t newfile_size = 0; + if (rdwr & RRD_CREAT) { + newfile_size = (off_t) rrd->stat_head->float_cookie; + free(rrd->stat_head); + } rrd_init(rrd); rrd_file = malloc(sizeof(rrd_file_t)); if (rrd_file == NULL) { @@ -196,17 +204,23 @@ rrd_file_t *rrd_open( if ((rrd_file->fd = open(file_name, flags, mode)) < 0) { rrd_set_error("opening '%s': %s", file_name, rrd_strerror(errno)); - return NULL; + goto out_free; } /* Better try to avoid seeks as much as possible. stat may be heavy but * many concurrent seeks are even worse. */ - if ((fstat(rrd_file->fd, &statb)) < 0) { + if (newfile_size == 0 && ((fstat(rrd_file->fd, &statb)) < 0)) { rrd_set_error("fstat '%s': %s", file_name, rrd_strerror(errno)); goto out_close; } - rrd_file->file_len = statb.st_size; - + if (newfile_size == 0) { + rrd_file->file_len = statb.st_size; + } else { + rrd_file->file_len = newfile_size; + lseek(rrd_file->fd, newfile_size - 1, SEEK_SET); + write(rrd_file->fd, "\0", 1); /* poke */ + lseek(rrd_file->fd, 0, SEEK_SET); + } #ifdef HAVE_POSIX_FADVISE /* In general we need no read-ahead when dealing with rrd_files. When we stop reading, it is highly unlikely that we start up again. @@ -234,37 +248,39 @@ rrd_file_t *rrd_open( /* lets see if the first read worked */ if (data == MAP_FAILED) { - rrd_set_error("error mmaping file '%s': %s", file_name, + rrd_set_error("mmaping file '%s': %s", file_name, rrd_strerror(errno)); goto out_close; } rrd_file->file_start = data; + if (rdwr & RRD_CREAT) { + memset(data, DNAN, newfile_size - 1); + goto out_done; + } #endif + if (rdwr & RRD_CREAT) + goto out_done; #ifdef USE_MADVISE if (rdwr & RRD_COPY) { /* We will read everything in a moment (copying) */ _madvise(data, rrd_file->file_len, MADV_WILLNEED | MADV_SEQUENTIAL); - goto out_done; - } - /* We do not need to read anything in for the moment */ -#ifndef ONE_PAGE - _madvise(data, rrd_file->file_len, MADV_DONTNEED); -// _madvise(data, rrd_file->file_len, MADV_RANDOM); -#else -/* alternatively: keep 2 pages worth of data, likely headers, - * don't need the rest. */ - _madvise(data, _page_size, MADV_WILLNEED | MADV_SEQUENTIAL); - _madvise(data + _page_size, (rrd_file->file_len >= _page_size) - ? rrd_file->file_len - _page_size : 0, MADV_DONTNEED); -#endif -#endif - -#if defined USE_MADVISE && !defined ONE_PAGE - /* the stat_head will be needed soonish, so hint accordingly */ -// too finegrained to calc the individual sizes, just keep 2 pages worth of hdr - _madvise(data + PAGE_ALIGN_DOWN(offset), PAGE_ALIGN(sizeof(stat_head_t)), - MADV_WILLNEED); + } else { +# ifndef ONE_PAGE + /* We do not need to read anything in for the moment */ + _madvise(data, rrd_file->file_len, MADV_DONTNEED); + /* the stat_head will be needed soonish, so hint accordingly */ + _madvise(data + PAGE_ALIGN_DOWN(offset), + PAGE_ALIGN(sizeof(stat_head_t)), + MADV_WILLNEED | MADV_RANDOM); +# else +/* alternatively: keep 1 page worth of data, likely headers, + * don't need the rest. */ + _madvise(data, _page_size, MADV_WILLNEED | MADV_SEQUENTIAL); + _madvise(data + _page_size, (rrd_file->file_len >= _page_size) + ? rrd_file->file_len - _page_size : 0, MADV_DONTNEED); +# endif + } #endif __rrd_read(rrd->stat_head, stat_head_t, @@ -277,7 +293,7 @@ rrd_file_t *rrd_open( } if (rrd->stat_head->float_cookie != FLOAT_COOKIE) { - rrd_set_error("This RRD was created on other architecture"); + rrd_set_error("This RRD was created on another architecture"); goto out_nullify_head; } @@ -341,17 +357,16 @@ rrd_file_t *rrd_open( __rrd_read(rrd->rra_ptr, rra_ptr_t, rrd->stat_head->rra_cnt); -#ifdef USE_MADVISE - out_done: -#endif rrd_file->header_len = offset; rrd_file->pos = offset; - + out_done: return (rrd_file); out_nullify_head: rrd->stat_head = NULL; out_close: close(rrd_file->fd); + out_free: + free(rrd_file); return NULL; } @@ -400,19 +415,19 @@ int rrd_close( #endif /* DEBUG */ #ifdef USE_MADVISE -#ifdef ONE_PAGE +# ifdef ONE_PAGE /* Keep headers around, round up to next page boundary. */ ret = PAGE_ALIGN(rrd_file->header_len % _page_size + rrd_file->header_len); if (rrd_file->file_len > ret) _madvise(rrd_file->file_start + ret, rrd_file->file_len - ret, MADV_DONTNEED); -#else +# else /* ignoring errors from RRDs that are smaller then the file_len+rounding */ _madvise(rrd_file->file_start + PAGE_ALIGN_DOWN(rrd_file->header_len), rrd_file->file_len - PAGE_ALIGN(rrd_file->header_len), MADV_DONTNEED); -#endif +# endif #endif #ifdef HAVE_MMAP ret = munmap(rrd_file->file_start, rrd_file->file_len); @@ -457,30 +472,40 @@ off_t rrd_seek( /* Get current position in rrd_file. */ -inline off_t rrd_tell(rrd_file_t *rrd_file) +inline off_t rrd_tell( + rrd_file_t *rrd_file) { return rrd_file->pos; } /* read count bytes into buffer buf, starting at rrd_file->pos. - * Returns the number of bytes read. */ + * Returns the number of bytes read or <0 on error. */ -ssize_t rrd_read( +inline ssize_t rrd_read( rrd_file_t *rrd_file, void *buf, size_t count) { #ifdef HAVE_MMAP - buf = memmove(buf, rrd_file->file_start + rrd_file->pos, count); - rrd_file->pos += count; /* mimmic read() semantics */ - return count; + size_t _cnt = count; + ssize_t _surplus = rrd_file->pos + _cnt - rrd_file->file_len; + + if (_surplus > 0) { /* short read */ + _cnt -= _surplus; + } + if (_cnt == 0) + return 0; /* EOF */ + buf = memcpy(buf, rrd_file->file_start + rrd_file->pos, _cnt); + + rrd_file->pos += _cnt; /* mimmic read() semantics */ + return _cnt; #else ssize_t ret; ret = read(rrd_file->fd, buf, count); - //XXX: eventually add generic rrd_set_error(""); here - rrd_file->pos += count; /* mimmic read() semantics */ + if (ret > 0) + rrd_file->pos += ret; /* mimmic read() semantics */ return ret; #endif } @@ -490,16 +515,21 @@ ssize_t rrd_read( * rrd_file->pos of rrd_file->fd. * Returns the number of bytes written. */ -ssize_t rrd_write( +inline ssize_t rrd_write( rrd_file_t *rrd_file, const void *buf, size_t count) { #ifdef HAVE_MMAP - memmove(rrd_file->file_start + rrd_file->pos, buf, count); + memcpy(rrd_file->file_start + rrd_file->pos, buf, count); + rrd_file->pos += count; return count; /* mimmic write() semantics */ #else - return write(rrd_file->fd, buf, count); + ssize_t _sz = write(rrd_file->fd, buf, count); + + if (_sz > 0) + rrd_file->pos += _sz; + return _sz; #endif } @@ -536,13 +566,14 @@ void rrd_init( #ifdef HAVE_MMAP inline void rrd_free( - rrd_t UNUSED(*rrd)) {} + rrd_t UNUSED(*rrd)) +{ +} #else void rrd_free( rrd_t *rrd) { - if (atoi(rrd->stat_head->version) < 3) - free(rrd->live_head); + free(rrd->live_head); free(rrd->stat_head); free(rrd->ds_def); free(rrd->rra_def);