diff options
| -rw-r--r-- | omar.c | 132 |
1 files changed, 75 insertions, 57 deletions
@@ -37,36 +37,30 @@ #include <stddef.h> #include <assert.h> #include <dirent.h> +#include <string.h> +#define ALIGN_UP(value, align) (((value) + (align)-1) & ~((align)-1)) +#define BLOCK_SIZE 512 + +static int outfd; static const char *inpath = NULL; static const char *outpath = NULL; /* - * OMAR state machine. - * - * @outfd: Output file descriptor. - * @inbuf: Input file buffer. - * @pos: Position in input file. - */ -struct omar_state { - int infd; - char *inbuf; - off_t pos; -}; - -/* * The OMAR file header, describes the basics * of a file. * - * @name: Name of the file (*not* the full path) + * @magic: Header magic ("OMAR") + * @nextptr: Offset from start of archive to next header * @len: Length of the file - * @next_hdr: Offset from start of archive to next header + * @namelen: Length of the filename */ struct omar_hdr { - char *name; - size_t len; - off_t next_hdr; -}; + char magic[4]; + uint32_t nextptr; + uint32_t len; + uint8_t namelen; +} __attribute__((packed)); static inline void help(void) @@ -78,49 +72,70 @@ help(void) printf("--------------------------------------\n"); } -static void -state_destroy(struct omar_state *stp) -{ - close(stp->infd); - if (stp->inbuf != NULL) { - free(stp->inbuf); - } -} - +/* + * Push a file into the archive output + * + * @pathname: Full path name of file + * @name: Name of file + */ static int -state_init(struct omar_state *res) +file_push(const char *pathname, const char *name) { + struct omar_hdr hdr; struct stat sb; - int retval = 0; + int infd, rem, error; + int pad_len; + char *buf; - assert(res != NULL); - res->infd = open(inpath, O_RDONLY); - if (res->infd < 0) { + /* Attempt to open the input file */ + if ((infd = open(pathname, O_RDONLY)) < 0) { perror("open"); - fprintf(stderr, "omar: failed to open input file\n"); - return res->infd; - } - - if ((retval = fstat(res->infd, &sb)) < 0) { - perror("fstat"); - fprintf(stderr, "omar: failed to stat input file\n"); - close(res->infd); - return retval; + return infd; } - if (!S_ISDIR(sb.st_mode)) { - fprintf(stderr, "omar: input file is not a directory\n"); - close(res->infd); - return -ENOTDIR; + if ((error = fstat(infd, &sb)) < 0) { + return error; } - res->inbuf = malloc(sb.st_size); - if (res->inbuf == NULL) { - close(res->infd); - fprintf(stderr, "omar: failed to allocate inbuf\n"); + /* Create and write the header */ + hdr.len = sb.st_size; + hdr.namelen = strlen(name); + memcpy(hdr.magic, "OMAR", sizeof(hdr.magic)); + hdr.nextptr = sizeof(hdr) + ALIGN_UP(hdr.len, BLOCK_SIZE); + write(outfd, &hdr, sizeof(hdr)); + write(outfd, name, hdr.namelen); + + /* We need the file data now */ + buf = malloc(hdr.len); + if (buf == NULL) { + printf("out of memory\n"); + close(infd); return -ENOMEM; } + if (read(infd, buf, hdr.len) <= 0) { + perror("read"); + close(infd); + return -EIO; + } + /* + * Write the actual file contents, if + * the file length is not a multiple + * of the block size, we'll need to + * pad out the rest to zero + */ + write(outfd, buf, hdr.len); + rem = hdr.len & (BLOCK_SIZE - 1); + if (rem != 0) { + /* Compute the padding length */ + pad_len = BLOCK_SIZE - rem; + + buf = realloc(buf, pad_len); + memset(buf, 0, pad_len); + write(outfd, buf, pad_len); + } + close(infd); + free(buf); return 0; } @@ -149,8 +164,10 @@ archive_create(const char *base) snprintf(pathbuf, sizeof(pathbuf), "%s/%s", base, ent->d_name); if (ent->d_type == DT_DIR) { archive_create(pathbuf); + } else if (ent->d_type == DT_REG) { + printf("%s\n", ent->d_name); + file_push(pathbuf, ent->d_name); } - printf("%s\n", pathbuf); } return 0; @@ -159,9 +176,8 @@ archive_create(const char *base) int main(int argc, char **argv) { - struct omar_state st = {0}; int optc, retval; - int error; + int error, flags; if (argc < 2) { help(); @@ -196,12 +212,14 @@ main(int argc, char **argv) return -1; } - if ((error = state_init(&st)) != 0) { - printf("omar: failed to init state\n"); - return error; + flags = S_IRUSR | S_IWUSR; + outfd = open(outpath, O_WRONLY | O_CREAT, flags); + if (outfd < 0) { + printf("omar: failed to open output file\n"); + return outfd; } retval = archive_create(inpath); - state_destroy(&st); + close(outfd); return retval; } |