X-Git-Url: http://git.draconx.ca/gitweb/liblbx.git/blobdiff_plain/ebf92322de06b5ece1724279d7f756077caa1438..a6ae4dd126e7b2b678e0db31b68bba51311282cc:/src/lbx.c diff --git a/src/lbx.c b/src/lbx.c index ef4589d..4b5d7f3 100644 --- a/src/lbx.c +++ b/src/lbx.c @@ -30,140 +30,91 @@ #include #include -#include "byteorder.h" +#include "pack.h" #include "misc.h" #include "lbx.h" -#define LBX_MAGIC 0x0000fead +#define LBX_MAGIC 0x0000fead +#define LBX_HDR_SIZE 8 int lbx_errno = 0; struct lbx_state { const char *name; - unsigned char *mem; - size_t memsize; - FILE *f; - long foff; + const struct lbx_file_ops *fops; + int (*dtor)(void *handle); + void *f; uint16_t nfiles; uint32_t offsets[]; }; -struct lbx_state *lbx_fopen(FILE *f, const char *name) +static struct lbx_state *lbx_init(unsigned char hdr[static LBX_HDR_SIZE]) { - struct lbx_state *new = NULL; - uint16_t nfiles, version; - uint32_t magic; - - if (fread(&nfiles, sizeof nfiles, 1, f) != 1) goto readerr; - if (fread(&magic, sizeof magic, 1, f) != 1) goto readerr; - if (fread(&version, sizeof version, 1, f) != 1) goto readerr; - - nfiles = letohs(nfiles); - magic = letohl(magic); - version = letohs(version); + unsigned short nfiles = unpack_16_le(hdr+0); + unsigned long magic = unpack_32_le(hdr+2); + unsigned short version = unpack_16_le(hdr+6); + struct lbx_state *lbx; if (magic != LBX_MAGIC) { - lbx_errno = LBX_EMAGIC; + lbx_errno = -LBX_EMAGIC; return NULL; } - - new = malloc(sizeof *new + (nfiles+1)*(sizeof *new->offsets)); - if (!new) { + + lbx = malloc(sizeof *lbx + sizeof lbx->offsets[0] * (nfiles+1)); + if (!lbx) { lbx_errno = -errno; return NULL; } - - *new = (struct lbx_state){ - .name = name, + + *lbx = (struct lbx_state) { .nfiles = nfiles, - .f = f, - .foff = sizeof nfiles + sizeof magic + sizeof version, }; - - if (fread(new->offsets, sizeof *new->offsets, nfiles+1, f) != nfiles+1) - goto readerr; - new->foff += sizeof *new->offsets * (nfiles+1); - - return new; -readerr: - if (feof(f)) { - lbx_errno = LBX_EEOF; - } else { - lbx_errno = -errno; - } - free(new); - return NULL; + return lbx; } -static int _lbx_memcpy(void *dest, struct lbx_state *src, size_t size) +struct lbx_state *lbx_open(void *f, const struct lbx_file_ops *fops, + int (*destructor)(void *), const char *name) { - if (src->foff + size > src->memsize) - return -1; - memcpy(dest, src->mem + src->foff, size); - src->foff += size; - return 0; -} - -struct lbx_state *lbx_mopen(void *_mem, size_t size, const char *name) -{ - struct lbx_state *new = NULL; - struct lbx_state tmp = { .mem = _mem, .memsize = size }; - uint16_t nfiles, version; - uint32_t magic; + unsigned char hdr_buf[LBX_HDR_SIZE]; + struct lbx_state *lbx; - if (_lbx_memcpy(&nfiles, &tmp, sizeof nfiles) == -1) goto eof; - if (_lbx_memcpy(&magic, &tmp, sizeof magic) == -1) goto eof; - if (_lbx_memcpy(&version, &tmp, sizeof version) == -1) goto eof; - - nfiles = letohs(nfiles); - magic = letohl(magic); - version = letohs(version); - - if (magic != LBX_MAGIC) { - lbx_errno = LBX_EMAGIC; + if (fops->read(hdr_buf, sizeof hdr_buf, f) != sizeof hdr_buf) { + lbx_errno = -errno; return NULL; } - - new = malloc(sizeof *new + (nfiles+1)*(sizeof *new->offsets)); - if (!new) { - lbx_errno = -errno; + + lbx = lbx_init(hdr_buf); + if (!lbx) return NULL; + + lbx->dtor = destructor; + lbx->name = name; + lbx->fops = fops; + lbx->f = f; + + for (unsigned i = 0; i <= lbx->nfiles; i++) { + unsigned char buf[4]; + + if (fops->read(buf, sizeof buf, f) != sizeof buf) { + lbx_errno = -errno; + if (fops->eof(f)) + lbx_errno = LBX_EEOF; + free(lbx); + return NULL; + } + + lbx->offsets[i] = unpack_32_le(buf); } - - *new = (struct lbx_state){ - .name = name, - .nfiles = nfiles, - .mem = _mem, - .memsize = size, - .foff = tmp.foff, - }; - - if (_lbx_memcpy(new->offsets, new, (nfiles+1)*(sizeof *new->offsets))) - goto eof; - - return new; -eof: - free(new); - lbx_errno = LBX_EEOF; - return NULL; + + return lbx; } -struct lbx_state *lbx_open(const char *path) +struct lbx_state *lbx_fopen(FILE *f, const char *name) { - struct lbx_state *new = NULL; - FILE *f; - - if ((f = fopen(path, "rb"))) { - const char *name = strrchr(path, '/'); - new = lbx_fopen(f, name ? name+1 : path); - } else { - lbx_errno = -errno; - } - - return new; + return lbx_open(f, &lbx_default_fops, NULL, name); } size_t lbx_numfiles(struct lbx_state *lbx) @@ -181,27 +132,12 @@ int lbx_stat(struct lbx_state *lbx, size_t index, struct lbx_statbuf *buf) return -1; } - snprintf(str, sizeof str, "%s.%03d", lbx->name, index); + snprintf(str, sizeof str, "%s.%03zu", lbx->name, index); buf->name = str; buf->size = lbx->offsets[index+1] - lbx->offsets[index]; return 0; } -static size_t -_lbx_mextract(struct lbx_state *lbx, size_t base, size_t len, FILE *of) -{ - size_t rc; - - assert(lbx->mem); - assert(base + len <= lbx->memsize); - - rc = fwrite(lbx->mem + base, 1, len, of); - if (rc < len) - lbx_errno = -errno; - - return rc; -} - static size_t _lbx_fextract(struct lbx_state *lbx, size_t base, size_t len, FILE *of) { @@ -210,17 +146,18 @@ _lbx_fextract(struct lbx_state *lbx, size_t base, size_t len, FILE *of) assert(lbx->f); - if (_lbx_fseek(lbx->f, &lbx->foff, base) == -1) + if (lbx->fops->seek(lbx->f, base, SEEK_SET) != 0) { + lbx_errno = -errno; return 0; + } while (len) { size_t amt = MIN(len, sizeof buf); - rc = fread(buf, 1, amt, lbx->f); - lbx->foff += rc; + rc = lbx->fops->read(buf, amt, lbx->f); len -= rc; if (rc < amt) { - if (feof(lbx->f)) lbx_errno = LBX_EEOF; + if (lbx->fops->eof(lbx->f)) lbx_errno = LBX_EEOF; else lbx_errno = -errno; break; } @@ -247,57 +184,18 @@ size_t lbx_extract(struct lbx_state *lbx, size_t index, FILE *of) base = lbx->offsets[index]; len = lbx->offsets[index+1] - lbx->offsets[index]; - - if (lbx->mem) - return _lbx_mextract(lbx, base, len, of); return _lbx_fextract(lbx, base, len, of); } -void *lbx_mmap(struct lbx_state *lbx, size_t index, size_t *len) +int lbx_close(struct lbx_state *lbx) { - unsigned char *mapping; - struct stat statbuf; - size_t base; - - if (index >= lbx->nfiles) { - lbx_errno = LBX_ERANGE; - return NULL; - } - - base = lbx->offsets[index]; - *len = lbx->offsets[index+1] - lbx->offsets[index]; - - if (lbx->mem) - return lbx->mem + base; - - if (fstat(fileno(lbx->f), &statbuf) == -1) { - lbx_errno = -errno; - return NULL; - } - - mapping = mmap(NULL, statbuf.st_size, PROT_READ, 0, fileno(lbx->f), 0); - if (mapping == MAP_FAILED) { - lbx_errno = -errno; - return NULL; - } - - lbx->mem = mapping; - lbx->memsize = statbuf.st_size; - return mapping + base; -} - -void lbx_close(struct lbx_state *lbx) -{ - if (!lbx) return; - - if (lbx->f) { - fclose(lbx->f); - if (lbx->mem) { - munmap(lbx->mem, lbx->memsize); - } - } + int rc = 0; + if (lbx && lbx->dtor) + rc = lbx->dtor(lbx->f); free(lbx); + + return rc; } const char *lbx_strerror(void)