diff options
| -rw-r--r-- | omar.c | 59 |
1 files changed, 37 insertions, 22 deletions
@@ -41,8 +41,13 @@ #include <string.h> #include <libgen.h> -/* OMAR type flags (TODO: rwx) */ -#define OMAR_DIR (1 << 0) +/* OMAR magic constants */ +#define OMAR_MAGIC "OMAR" +#define OMAR_EOF "RAMO" + +/* OMAR type constants */ +#define OMAR_REG 0 +#define OMAR_DIR 1 #define ALIGN_UP(value, align) (((value) + (align)-1) & ~((align)-1)) #define BLOCK_SIZE 512 @@ -56,16 +61,14 @@ static const char *outpath = NULL; * of a file. * * @magic: Header magic ("OMAR") - * @nextptr: Offset from start of archive to next header * @len: Length of the file * @namelen: Length of the filename */ struct omar_hdr { char magic[4]; - uint16_t type; - uint32_t nextptr; - uint32_t len; + uint8_t type; uint8_t namelen; + uint32_t len; } __attribute__((packed)); static inline void @@ -91,8 +94,11 @@ file_push(const char *pathname, const char *name) struct stat sb; int infd, rem, error; int pad_len; + size_t len; char *buf; + hdr.type = OMAR_REG; + /* Attempt to open the input file if not EOF */ if (pathname != NULL) { if ((infd = open(pathname, O_RDONLY)) < 0) { @@ -103,36 +109,44 @@ file_push(const char *pathname, const char *name) if ((error = fstat(infd, &sb)) < 0) { return error; } + + if (S_ISDIR(sb.st_mode)) { + hdr.type = OMAR_DIR; + } } - /* Set the lengths */ hdr.len = (pathname == NULL) ? 0 : sb.st_size; hdr.namelen = strlen(name); /* - * The next pointer being 0 indicates that we - * have reached the end of the archive. If we - * haven't reached the end of the file, compute - * the next header offset. + * If we are at the end of the file, use the OMAR_EOF + * magic constant instant of the usual OMAR_MAGIC. */ - if (pathname != NULL) { - hdr.nextptr = sizeof(hdr) + ALIGN_UP(hdr.len, BLOCK_SIZE); - printf("NEXT POINTER: %d\n", hdr.nextptr); + if (pathname == NULL) { + memcpy(hdr.magic, OMAR_EOF, sizeof(hdr.magic)); } else { - hdr.nextptr = 0; + memcpy(hdr.magic, OMAR_MAGIC, sizeof(hdr.magic)); } - memcpy(hdr.magic, "OMAR", sizeof(hdr.magic)); + write(outfd, &hdr, sizeof(hdr)); write(outfd, name, hdr.namelen); + + /* If we are at the end of file, we are done */ if (pathname == NULL) { - /* EOF, we are done */ + close(infd); return 0; } - /* If this is a dir, our work is done here */ - if (S_ISDIR(sb.st_mode)) { - hdr.type |= OMAR_DIR; - close(infd); + /* Pad directories to zero */ + if (hdr.type == OMAR_DIR) { + len = sizeof(hdr) + hdr.namelen; + rem = len & (BLOCK_SIZE - 1); + pad_len = BLOCK_SIZE - rem; + + buf = malloc(pad_len); + memset(buf, 0, pad_len); + write(outfd, buf, pad_len); + free(buf); return 0; } @@ -155,7 +169,8 @@ file_push(const char *pathname, const char *name) * to zero. */ write(outfd, buf, hdr.len); - rem = hdr.len & (BLOCK_SIZE - 1); + len = sizeof(hdr) + (hdr.namelen + hdr.len); + rem = len & (BLOCK_SIZE - 1); if (rem != 0) { /* Compute the padding length */ pad_len = BLOCK_SIZE - rem; |