From 3c090cf56c2ac6f5cb656508c9dd311555a98f41 Mon Sep 17 00:00:00 2001 From: June McEnroe Date: Sat, 24 Nov 2018 23:41:11 -0500 Subject: Implement deserialization in edi --- bin/edi/store.c | 193 +++++++++++++++++++++++++++++++++++++++++++++----------- 1 file changed, 156 insertions(+), 37 deletions(-) (limited to 'bin/edi/store.c') diff --git a/bin/edi/store.c b/bin/edi/store.c index f32ef297..d7b4e71e 100644 --- a/bin/edi/store.c +++ b/bin/edi/store.c @@ -15,7 +15,7 @@ */ #include -#include +#include #include #include #include @@ -25,68 +25,187 @@ static const char Magic[3] = "EDI"; static const char Version = 1; -static bool writeBuffer(FILE *stream, const struct Buffer *buf) { +static enum Error +write(FILE *stream, const void *ptr, size_t size, size_t nitems) { + size_t n = fwrite(ptr, size, nitems, stream); + return (n < nitems ? Errno + errno : Ok); +} + +static enum Error writeBuffer(FILE *stream, const struct Buffer *buf) { size_t len = 0; const struct Block *block; for (block = buf->block; block; block = block->prev) { len += block->len; } - if (!fwrite(&len, sizeof(len), 1, stream)) return false; + enum Error error = write(stream, &len, sizeof(len), 1); + if (error) return error; for (block = buf->block; block; block = block->prev) { - fwrite(block->chars, sizeof(wchar_t), block->len, stream); - if (ferror(stream)) return false; + error = write(stream, block->chars, sizeof(wchar_t), block->len); + if (error) return error; } - return true; + return Ok; } -static bool writeSlice( - FILE *stream, const struct Buffer *buf, struct Slice slice -) { +static enum Error +writeSlice(FILE *stream, const struct Buffer *buf, struct Slice slice) { size_t offset = 0; - const struct Block *block; - for (block = buf->block; block; offset += block->len, block = block->prev) { + const struct Block *block = buf->block; + while (block) { if ( slice.ptr >= block->chars && slice.ptr < &block->chars[block->len] ) break; + offset += block->len; + block = block->prev; } assert(block); size_t ptr = offset + (size_t)(slice.ptr - block->chars); - return fwrite(&ptr, sizeof(ptr), 1, stream) - && fwrite(&slice.len, sizeof(slice.len), 1, stream); + enum Error error = write(stream, &ptr, sizeof(ptr), 1); + if (error) return error; + return write(stream, &slice.len, sizeof(slice.len), 1); } -static bool writeTable( - FILE *stream, const struct Buffer *buf, const struct Table *table -) { - if (!fwrite(&table->len, sizeof(table->len), 1, stream)) return false; +static enum Error +writeTable(FILE *stream, const struct Buffer *buf, const struct Table *table) { + enum Error error = write(stream, &table->len, sizeof(table->len), 1); for (size_t i = 0; i < table->len; ++i) { - if (!writeSlice(stream, buf, table->slices[i])) return false; + error = writeSlice(stream, buf, table->slices[i]); + if (error) return error; } - return true; + return Ok; } -static bool writeState( - FILE *stream, const struct Buffer *buf, const struct State *state -) { - return fwrite(&state->prev, sizeof(state->prev), 1, stream) - && fwrite(&state->next, sizeof(state->next), 1, stream) - && writeTable(stream, buf, &state->table); +static enum Error +writeState(FILE *stream, const struct Buffer *buf, const struct State *state) { + enum Error error; + error = write(stream, &state->prev, sizeof(state->prev), 1); + if (error) return error; + error = write(stream, &state->next, sizeof(state->next), 1); + if (error) return error; + return writeTable(stream, buf, &state->table); } -static bool writeLog( - FILE *stream, const struct Buffer *buf, const struct Log *log -) { - if (!fwrite(&log->state, sizeof(log->state), 1, stream)) return false; - if (!fwrite(&log->len, sizeof(log->len), 1, stream)) return false; +static enum Error +writeLog(FILE *stream, const struct Buffer *buf, const struct Log *log) { + enum Error error; + error = write(stream, &log->state, sizeof(log->state), 1); + if (error) return error; + error = write(stream, &log->len, sizeof(log->len), 1); + if (error) return error; for (size_t i = 0; i < log->len; ++i) { - if (!writeState(stream, buf, &log->states[i])) return false; + error = writeState(stream, buf, &log->states[i]); + if (error) return error; + } + return Ok; +} + +enum Error storeWrite(FILE *stream, const struct Edit *edit) { + enum Error error; + error = write(stream, Magic, sizeof(Magic), 1); + if (error) return error; + error = write(stream, &Version, sizeof(Version), 1); + if (error) return error; + error = writeBuffer(stream, &edit->buf); + if (error) return error; + return writeLog(stream, &edit->buf, &edit->log); +} + +static enum Error read(FILE *stream, void *ptr, size_t size, size_t nitems) { + size_t n = fread(ptr, size, nitems, stream); + if (ferror(stream)) return Errno + errno; + return (n < nitems ? StoreEOF : Ok); +} + +static enum Error readMagic(FILE *stream) { + char magic[3]; + enum Error error = read(stream, magic, sizeof(magic), 1); + if (error) return error; + return ( + magic[0] != Magic[0] || magic[1] != Magic[1] || magic[2] != Magic[2] + ? StoreMagic + : Ok + ); +} + +static enum Error readVersion(FILE *stream) { + char version; + enum Error error = read(stream, &version, sizeof(version), 1); + if (error) return error; + return (version != Version ? StoreVersion : Ok); +} + +static enum Error readBuffer(FILE *stream, struct Buffer *buf) { + size_t len; + enum Error error = read(stream, &len, sizeof(len), 1); + if (error) return error; + wchar_t *dest = bufferDest(buf, len); + return read(stream, dest, sizeof(wchar_t), len); +} + +static enum Error +readSlice(FILE *stream, struct Buffer *buf, struct Table *table) { + enum Error error; + size_t ptr, len; + error = read(stream, &ptr, sizeof(ptr), 1); + if (error) return error; + error = read(stream, &len, sizeof(len), 1); + if (error) return error; + tablePush(table, (struct Slice) { &buf->slice.ptr[ptr], len }); + return Ok; +} + +static enum Error +readTable(FILE *stream, struct Buffer *buf, struct Table *table) { + size_t len; + enum Error error = read(stream, &len, sizeof(len), 1); + if (error) return error; + *table = tableAlloc(len); + for (size_t i = 0; i < len; ++i) { + error = readSlice(stream, buf, table); + if (error) return error; + } + return Ok; +} + +static enum Error +readState(FILE *stream, struct Buffer *buf, size_t offset, struct Log *log) { + enum Error error; + size_t prev, next; + struct Table table; + error = read(stream, &prev, sizeof(prev), 1); + if (error) return error; + error = read(stream, &next, sizeof(next), 1); + if (error) return error; + error = readTable(stream, buf, &table); + if (error) return error; + logPush(log, table); + log->states[log->state].prev = offset + prev; + log->states[log->state].next = offset + next; + return Ok; +} + +static enum Error readLog(FILE *stream, struct Buffer *buf, struct Log *log) { + enum Error error; + size_t state, len; + error = read(stream, &state, sizeof(state), 1); + if (error) return error; + error = read(stream, &len, sizeof(len), 1); + if (error) return error; + size_t offset = log->len; + for (size_t i = 0; i < len; ++i) { + error = readState(stream, buf, offset, log); + if (error) return error; } - return true; + log->state = offset + state; + return Ok; } -bool storeWrite(FILE *stream, const struct Edit *edit) { - return fwrite(Magic, sizeof(Magic), 1, stream) - && fwrite(&Version, sizeof(Version), 1, stream) - && writeBuffer(stream, &edit->buf) - && writeLog(stream, &edit->buf, &edit->log); +enum Error storeRead(FILE *stream, struct Edit *edit) { + enum Error error; + error = readMagic(stream); + if (error) return error; + error = readVersion(stream); + if (error) return error; + error = readBuffer(stream, &edit->buf); + if (error) return error; + return readLog(stream, &edit->buf, &edit->log); } -- cgit 1.4.1