scc

ar.c (11614B)

---

 #include <errno.h>
 #include <signal.h>
 #include <stdarg.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <time.h>
 
 #include <scc/ar.h>
 #include <scc/scc.h>
 #include <scc/arg.h>
 
 enum {
 	BEFORE,
 	INDOT,
 	AFTER,
 };
 
 struct tmp {
 	char *name;
 	FILE *fp;
 } tmps[3];
 
 char *argv0;
 
 static int bflag, vflag, cflag, lflag, uflag, aflag;
 static char *arfile, *posname;
 static char invalidchars[] = " ";
 
 struct member {
 	FILE *src;
 	struct ar_hdr hdr;
 	int cur;
 	char *fname;
 	long size;
 	long mode;
 	long long date;
 };
 
 /*
  * Best effort to try avoid calling remove from a signal
  * handler is to detect that we are in an UNIX
  * system and redirect with the preprocessor remove
  * to unlink that is defined as signal safe.
  */
 #if defined(__unix) || defined(__unix__)
 #include <unistd.h>
 #undef remove
 #define remove unlink
 #endif
 
 static void
 cleanup(void)
 {
 	int i;
 
 	for (i = 0; i < 3; i++) {
 		if (tmps[i].name)
 			remove(tmps[i].name);
 	}
 }
 
 #undef remove
 
 static char *
 errstr(void)
 {
 	return strerror(errno);
 }
 
 static void
 error(char *fmt, ...)
 {
 	va_list va;
 
 	va_start(va, fmt);
 	fprintf(stderr, "ar: %s: ", arfile);
 	vfprintf(stderr, fmt, va);
 	putc('\n', stderr);
 	va_end(va);
 
 	exit(EXIT_FAILURE);
 }
 
 /*
  * I do know that you cannot call remove from a signal handler
  * but we only can use stdio function to deal with files
  * because we are C99 compliant, and it is very likely that
  * remove is going to work in this case
  */
 static void
 sigfun(int signum)
 {
 	cleanup();
 	_Exit(1);
 }
 
 static FILE *
 openar(void)
 {
 	FILE *fp;
 	char magic[SARMAG+1];
 
 	if ((fp = fopen(arfile,"r+b")) == NULL) {
 		if (!cflag)
 			fprintf(stderr, "ar: creating %s\n", arfile);
 		if ((fp = fopen(arfile, "w+b")) == NULL)
 			error("opening archive: %s", errstr());
 		fputs(ARMAG, fp);
 		if (fflush(fp) == EOF)
 			error("writing magic number: %s", errstr());
 	} else {
 		if (fgets(magic, sizeof(magic), fp) == NULL)
 			error("error reading magic number: %s", errstr());
 		if (strcmp(magic, ARMAG))
 			error("invalid magic number '%s'", magic);
 	}
 	return fp;
 }
 
 static void
 archive(char *pname, FILE *to, char letter)
 {
 	int c;
 	FILE *from;
 	char *fname;
 	struct fprop prop;
 
 	fname = canonical(pname);
 
 	if (vflag)
 		printf("%c - %s\n", letter, fname);
 	if ((from = fopen(pname, "rb")) == NULL)
 		error("opening member '%s': %s", pname, errstr());
 	if (getstat(pname, &prop) < 0)
 		error("error getting '%s' attributes", pname);
 
 	fprintf(to,
 	        "%-16.16s%-12lld%-6u%-6u%-8lo%-10ld`\n",
 	        fname,
 	        fromepoch(prop.time),
 	        prop.uid,
 	        prop.gid,
 	        prop.mode,
 	        prop.size);
 
 	while ((c = getc(from)) != EOF)
 		putc(c, to);
 	if (prop.size & 1)
 		putc('\n', to);
 	if (ferror(from))
 		error("reading input '%s': %s", pname, errstr());
 	fclose(from);
 }
 
 static void
 append(FILE *fp, char *argv[])
 {
 	char *fname;
 
 	if (fseek(fp, 0, SEEK_END) == EOF)
 		error("seeking archive: %s", errstr());
 
 	for ( ; fname = *argv; ++argv) {
 		*argv = NULL;
 		archive(fname, fp, 'a');
 	}
 
 	if (fclose(fp) == EOF)
 		error("error writing archive: %s", errstr());
 }
 
 static void
 copy(struct member *m, struct tmp *tmp)
 {
 	int c;
 	size_t siz = m->size;
 	struct ar_hdr *hdr = &m->hdr;
 
 	fwrite(hdr, sizeof(*hdr), 1, tmp->fp);
 	if ((siz & 1) == 1)
 		siz++;
 	while (siz--) {
 		if ((c = getc(m->src)) == EOF)
 			break;
 		fputc(c, tmp->fp);
 	}
 }
 
 static void
 letters(unsigned long val, char *s)
 {
 	*s++ = (val & 04) ? 'r' : '-';
 	*s++ = (val & 02) ? 'w' : '-';
 	*s++ = (val & 01) ? 'x' : '-';
 }
 
 static char *
 perms(struct member *m)
 {
 	static char buf[10];
 
 	letters(m->mode >> 6, buf);
 	letters(m->mode >> 3, buf+3);
 	letters(m->mode, buf +6);
 	buf[9] = '\0';
 
 	return buf;
 }
 
 static char *
 inlist(char *fname, int argc, char *argv[])
 {
 	char *p;
 
 	for ( ; argc-- > 0; ++argv) {
 		if (*argv && !strcmp(canonical(*argv), fname)) {
 			p = *argv;
 			*argv = NULL;
 			return p;
 		}
 	}
 	return NULL;
 }
 
 static int
 older(struct member *m, char *pname)
 {
 	struct fprop prop;
 
 	if (getstat(pname, &prop) < 0)
 		error("error getting '%s' attributes", pname);
 	return prop.time > m->date;
 }
 
 static void
 move(struct member *m, int argc, char *argv[])
 {
 	int where;
 
 	if (inlist(m->fname, argc, argv)) {
 		if (vflag)
 			printf("m - %s\n", m->fname);
 		where = INDOT;
 	} else if (posname && !strcmp(posname, m->fname)) {
 		where = (bflag) ? AFTER : BEFORE;
 		m->cur = AFTER;
 	} else {
 		where = m->cur;
 	}
 	copy(m, &tmps[where]);
 }
 
 static void
 insert(int argc, char *argv[])
 {
 	for (; argc-- > 0; ++argv) {
 		if (*argv) {
 			archive(*argv, tmps[INDOT].fp, 'a');
 			*argv = NULL;
 		}
 	}
 }
 
 static void
 update(struct member *m, int argc, char *argv[])
 {
 	int where;
 	FILE *fp = tmps[BEFORE].fp;
 	char *pname;
 
 	if (pname = inlist(m->fname, argc, argv)) {
 		if (!uflag || older(m, pname)) {
 			archive(pname, tmps[m->cur].fp, 'r');
 			return;
 		}
 	}
 
 	if (posname && !strcmp(posname, m->fname)) {
 		where = (bflag) ? AFTER : BEFORE;
 		m->cur = AFTER;
 	} else {
 		where = m->cur;
 	}
 	copy(m, &tmps[where]);
 }
 
 static void
 extract(struct member *m, int argc, char *argv[])
 {
 	int c;
 	long siz;
 	FILE *fp;
 	struct fprop prop;
 	struct ar_hdr *hdr = &m->hdr;
 
 	if (argc > 0 && !inlist(m->fname, argc, argv))
 		return;
 	if (vflag)
 		printf("x - %s\n", m->fname);
 	siz = m->size;
 
 	if ((fp = fopen(m->fname, "wb")) == NULL)
 		goto error_file;
 	while (siz-- > 0 && (c = getc(m->src)) != EOF)
 		putc(c, fp);
 	fflush(fp);
 	if (fclose(fp) == EOF)
 		goto error_file;
 
 	prop.uid = atol(hdr->ar_uid);
 	prop.gid = atol(hdr->ar_gid);
 	prop.mode = m->mode;
 	prop.time = totime(m->date);
 	if (setstat(m->fname, &prop) < 0)
 		error("%s: setting file attributes", m->fname);
 	return;
 
 error_file:
 	error("error extracting file: %s", errstr());
 }
 
 static void
 print(struct member *m, int argc, char *argv[])
 {
 	long siz;
 	int c;
 
 	if (argc > 0 && !inlist(m->fname, argc, argv))
 		return;
 	if (vflag)
 		printf("\n<%s>\n\n", m->fname);
 	siz = m->size;
 	while (siz-- > 0 && (c = getc(m->src)) != EOF)
 		putchar(c);
 }
 
 static void
 list(struct member *m, int argc, char *argv[])
 {
 	time_t t;
 	struct ar_hdr *hdr = &m->hdr;
 	char mtime[30];
 
 	if (argc > 0  && !inlist(m->fname, argc, argv))
 		return;
 	if (!vflag) {
 		printf("%s\n", m->fname);
 	} else {
 		t = totime(m->date);
 		strftime(mtime, sizeof(mtime), "%c", localtime(&t));
 		printf("%s %ld/%ld\t%s %s\n",
 		       perms(m),
 		       atol(hdr->ar_uid),
 		       atol(hdr->ar_gid),
 		       mtime,
 		       m->fname);
 	}
 }
 
 static void
 del(struct member *m, int argc, char *argv[])
 {
 	if (inlist(m->fname, argc, argv)) {
 		if (vflag)
 			printf("d - %s\n", m->fname);
 		return;
 	}
 	copy(m, &tmps[BEFORE]);
 }
 
 static char *
 getfname(struct ar_hdr *hdr)
 {
 	static char fname[SARNAM+1];
 	char *p;
 
 	memcpy(fname, hdr->ar_name, SARNAM);
 
 	if (p = strchr(fname, ' '))
 		*p = '\0';
 	else
 		fname[SARNAM] = '\0';
 
 	return fname;
 }
 
 static long long
 getnum(char *s, int size, int base)
 {
 	int c;
 	long long val;
 	char *p;
 	static char digits[] = "0123456789";
 
 	for (val = 0; size > 0; val += c) {
 		--size;
 		if ((c = *s++) == ' ')
 			break;
 		if ((p = strchr(digits, c)) == NULL)
 			return -1;
 		if ((c = p - digits) >= base)
 			return -1;
 		val *= base;
 	}
 
 	while (size > 0 && *s++ == ' ')
 		--size;
 	return (size == 0) ? val : -1;
 }
 
 static int
 valid(struct member *m)
 {
 	struct ar_hdr *hdr = &m->hdr;
 
 	m->fname = getfname(&m->hdr);
 	m->size = getnum(hdr->ar_size, sizeof(hdr->ar_size), 10);
 	m->mode = getnum(hdr->ar_mode, sizeof(hdr->ar_mode), 8);
 	m->date = getnum(hdr->ar_date, sizeof(hdr->ar_date), 10);
 
 	if (strncmp(hdr->ar_fmag, ARFMAG, sizeof(hdr->ar_fmag)) ||
 	    m->size < 0 || m->mode < 0 || m->date < 0) {
 		return 0;
 	}
 	return 1;
 }
 
 static void
 run(FILE *fp, int argc, char *argv[],
     void (*fun)(struct member *, int argc, char *files[]))
 {
 	struct member m;
 
 	m.src = fp;
 	m.cur = BEFORE;
 
 	while (fread(&m.hdr, sizeof(m.hdr), 1, fp) == 1) {
 		fpos_t pos;
 
 		if (!valid(&m))
 			error("corrupted member '%s'", m.fname);
 		fgetpos(fp, &pos);
 		(*fun)(&m, argc, argv);
 		fsetpos(fp, &pos);
 		fseek(fp, m.size+1 & ~1, SEEK_CUR);
 	}
 	if (ferror(fp))
 		error("reading members: %s", errstr());
 	fclose(fp);
 }
 
 static void
 merge(void)
 {
 	FILE *fp, *fi;
 	int c, i;
 
 	if ((fp = fopen(arfile, "wb")) == NULL)
 		error("reopening archive: %s", errstr());
 
 	fputs(ARMAG, fp);
 
 	for (i = 0; i < 3; i++) {
 		if ((fi = tmps[i].fp) == NULL)
 			continue;
 		fseek(fi, 0, SEEK_SET);
 		while ((c = getc(fi)) != EOF)
 			putc(c, fp);
 		if (ferror(fi))
 			error("error in temporary: %s", errstr());
 	}
 
 	if (fclose(fp) == EOF)
 		error("writing archive file: %s", errstr());
 }
 
 static void
 closetmp(int which)
 {
 	struct tmp *tmp = &tmps[which];
 
 	if (!tmp->fp)
 		return;
 	if (fclose(tmp->fp) == EOF)
 		error("closing temporaries: %s", errstr());
 }
 
 static void
 opentmp(char *fname, int which)
 {
 	struct tmp *tmp = &tmps[which];
 
 	if (lflag) {
 		tmp->name = fname;
 		tmp->fp = fopen(fname, "w+b");
 	} else {
 		tmp->fp = tmpfile();
 	}
 
 	if (tmp->fp == NULL)
 		error("creating temporary: %s", errstr());
 }
 
 static void
 ar(int key, char *argv[], int argc)
 {
 	FILE *fp;
 
 	fp = openar();
 	if (argc == 0 &&
 	    (key == 'r' || key == 'd' || key == 'm' || key == 'q')) {
 		if (fclose(fp) == EOF)
 			error("early close of archive file: %s", errstr());
 		return;
 	}
 
 	if (key == 'r' || key == 'm' || key == 'd')
 		opentmp("ar.tmp1", BEFORE);
 	if (key == 'r' || key == 'm') {
 		opentmp("ar.tmp2", INDOT);
 		opentmp("ar.tmp3", AFTER);
 	}
 
 	switch (key) {
 	case 'r':
 		run(fp, argc, argv, update);
 		insert(argc, argv);
 		merge();
 		break;
 	case 'm':
 		run(fp, argc, argv, move);
 		merge();
 		break;
 	case 'd':
 		run(fp, argc, argv, del);
 		merge();
 		break;
 	case 't':
 		run(fp, argc, argv, list);
 		break;
 	case 'p':
 		run(fp, argc, argv, print);
 		break;
 	case 'x':
 		run(fp, argc, argv, extract);
 		break;
 	case 'q':
 		append(fp, argv);
 		break;
 	}
 
 	closetmp(BEFORE);
 	closetmp(INDOT);
 	closetmp(AFTER);
 
 	for ( ; argc-- > 0; ++argv) {
 		if (*argv)
 			error("No member named '%s'", *argv);
 	}
 }
 
 static void
 checkfnames(int argc, char *argv[])
 {
 	size_t l;
 	char *p;
 
 	for ( ; argc-- > 0; ++argv) {
 		p = canonical(*argv);
 		l = strcspn(p, invalidchars);
 		if (l > 16)
 			error("file: '%s': name too long", *argv);
 		if (p[l] != '\0')
 			error("file: '%s': name invalid", *argv);
 	}
 }
 
 static void
 usage(void)
 {
 	fputs("ar [-drqtpmx][posname] [-vuaibcl] [posname] arfile name ...\n",
 	      stderr);
 	exit(1);
 }
 
 int
 main(int argc, char *argv[])
 {
 	int key, nkey = 0, pos = 0;
 
 	atexit(cleanup);
 	ARGBEGIN {
 	case 'd':
 		nkey++;
 		key = 'd';
 		break;
 	case 'r':
 		nkey++;
 		key = 'r';
 		break;
 	case 'q':
 		nkey++;
 		key = 'q';
 		break;
 	case 't':
 		nkey++;
 		key = 't';
 		break;
 	case 'p':
 		nkey++;
 		key = 'p';
 		break;
 	case 'm':
 		nkey++;
 		key = 'm';
 		break;
 	case 'x':
 		nkey++;
 		key = 'x';
 		break;
 	case 'a':
 		aflag = 1;
 		pos++;
 		posname = EARGF(usage());
 		break;
 	case 'i':
 	case 'b':
 		bflag = 1;
 		pos++;
 		posname = EARGF(usage());
 		break;
 	case 'v':
 		vflag = 1;
 		break;
 	case 'c':
 		cflag = 1;
 		break;
 	case 'l':
 		lflag = 1;
 		break;
 	case 'u':
 		uflag = 1;
 		break;
 	default:
 		usage();
 	} ARGEND
 
 	if (nkey == 0 || nkey > 1 || pos > 1 || argc == 0 ||
 	    (aflag || bflag) && !(key == 'm' || key == 'r') ||
 	    cflag && !(key == 'q' || key == 'r') ||
 	    uflag && key != 'r')
 		usage();
 
 	signal(SIGINT, sigfun);
 #ifdef SIGQUIT
 	signal(SIGQUIT, sigfun);
 #endif
 	signal(SIGTERM, sigfun);
 
 	arfile = *argv;
 	checkfnames(--argc, ++argv);
 	ar(key, argv, argc);
 
 	fflush(stdout);
 	if (ferror(stdout))
 		error("error writing to stdout: %s", errstr());
 
 	return 0;
 }