diff options
| -rw-r--r-- | ring.c | 39 |
1 files changed, 27 insertions, 12 deletions
diff --git a/ring.c b/ring.c index 3bd177d..2d41666 100644 --- a/ring.c +++ b/ring.c @@ -118,15 +118,23 @@ void ringInfo(void) { } } -static const size_t FileVersion[] = { +static const size_t Signatures[] = { 0x0165636E756F70, // no ring size 0x0265636E756F70, // time_t only + 0x0365636E756F70, }; +static size_t signatureVersion(size_t signature) { + for (size_t i = 0; i < ARRAY_LEN(Signatures); ++i) { + if (signature == Signatures[i]) return i; + } + errx(EX_DATAERR, "unknown file signature %zX", signature); +} + static int writeSize(FILE *file, size_t value) { return (fwrite(&value, sizeof(value), 1, file) ? 0 : -1); } -static int writeTime(FILE *file, time_t time) { +static int writeTime(FILE *file, struct timeval time) { return (fwrite(&time, sizeof(time), 1, file) ? 0 : -1); } static int writeString(FILE *file, const char *str) { @@ -134,7 +142,7 @@ static int writeString(FILE *file, const char *str) { } int ringSave(FILE *file) { - if (writeSize(file, FileVersion[1])) return -1; + if (writeSize(file, Signatures[2])) return -1; if (writeSize(file, ring.len)) return -1; if (writeSize(file, producer)) return -1; if (writeSize(file, consumers.len)) return -1; @@ -143,7 +151,7 @@ int ringSave(FILE *file) { if (writeSize(file, consumers.ptr[i].pos)) return -1; } for (size_t i = 0; i < ring.len; ++i) { - if (writeTime(file, ring.times[i].tv_sec)) return -1; + if (writeTime(file, ring.times[i])) return -1; } for (size_t i = 0; i < ring.len; ++i) { if (!ring.lines[i]) break; @@ -157,7 +165,12 @@ static void readSize(FILE *file, size_t *value) { if (ferror(file)) err(EX_IOERR, "fread"); if (feof(file)) err(EX_DATAERR, "unexpected eof"); } -static void readTime(FILE *file, time_t *time) { +static void readTime(FILE *file, struct timeval *time) { + fread(time, sizeof(*time), 1, file); + if (ferror(file)) err(EX_IOERR, "fread"); + if (feof(file)) err(EX_DATAERR, "unexpected eof"); +} +static void readTimeT(FILE *file, time_t *time) { fread(time, sizeof(*time), 1, file); if (ferror(file)) err(EX_IOERR, "fread"); if (feof(file)) err(EX_DATAERR, "unexpected eof"); @@ -168,16 +181,14 @@ static void readString(FILE *file, char **buf, size_t *cap) { } void ringLoad(FILE *file) { - size_t version; - fread(&version, sizeof(version), 1, file); + size_t signature; + fread(&signature, sizeof(signature), 1, file); if (ferror(file)) err(EX_IOERR, "fread"); if (feof(file)) return; - if (version != FileVersion[0] && version != FileVersion[1]) { - errx(EX_DATAERR, "unknown file version %zX", version); - } + size_t version = signatureVersion(signature); size_t saveLen = 4096; - if (version == FileVersion[1]) readSize(file, &saveLen); + if (version > 0) readSize(file, &saveLen); if (saveLen > ring.len) { errx(EX_DATAERR, "cannot load save with larger ring"); } @@ -196,7 +207,11 @@ void ringLoad(FILE *file) { } for (size_t i = 0; i < saveLen; ++i) { - readTime(file, &ring.times[i].tv_sec); + if (version < 2) { + readTimeT(file, &ring.times[i].tv_sec); + } else { + readTime(file, &ring.times[i]); + } } for (size_t i = 0; i < saveLen; ++i) { readString(file, &buf, &cap); |