libbb: introduce and use xrealloc_vector

function                                             old     new   delta
xrealloc_vector_helper                                 -      51     +51
create_list                                           84      99     +15
getopt_main                                          690     695      +5
passwd_main                                         1049    1053      +4
get_cached                                            85      89      +4
msh_main                                            1377    1380      +3
add_match                                             42      41      -1
read_lines                                           720     718      -2
grave                                               1068    1066      -2
fill_match_lines                                     143     141      -2
add_to_dirlist                                        67      65      -2
add_input_file                                        49      47      -2
act                                                  252     250      -2
fsck_main                                           2252    2246      -6
man_main                                             765     757      -8
bb_internal_initgroups                               228     220      -8
cut_main                                            1052    1041     -11
add_edge_to_node                                      55      43     -12
dpkg_main                                           3851    3835     -16
ifupdown_main                                       2202    2178     -24
sort_main                                            838     812     -26
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 5/15 up/down: 82/-124)          Total: -42 bytes

archival/dpkg.c

@@ -382,9 +382,8 @@ static int search_for_provides(int needle, int start_at)
  */
 static void add_edge_to_node(common_node_t *node, edge_t *edge)
 {
-	node->num_of_edges++;
-	node->edge = xrealloc(node->edge, sizeof(edge_t) * (node->num_of_edges + 1));
-	node->edge[node->num_of_edges - 1] = edge;
+	node->edge = xrealloc_vector(node->edge, 2, node->num_of_edges);
+	node->edge[node->num_of_edges++] = edge;
 }
 
 /*
@@ -972,7 +971,7 @@ static int check_deps(deb_file_t **deb_file, int deb_start /*, int dep_max_count
 	 * installed package for conflicts*/
 	while (deb_file[i] != NULL) {
 		const unsigned package_num = deb_file[i]->package;
-		conflicts = xrealloc(conflicts, sizeof(int) * (conflicts_num + 1));
+		conflicts = xrealloc_vector(conflicts, 2, conflicts_num);
 		conflicts[conflicts_num] = package_num;
 		conflicts_num++;
 		/* add provides to conflicts list */
@@ -989,7 +988,7 @@ static int check_deps(deb_file_t **deb_file, int deb_start /*, int dep_max_count
 					new_node->version = package_hashtable[package_num]->edge[j]->version;
 					package_hashtable[conflicts_package_num] = new_node;
 				}
-				conflicts = xrealloc(conflicts, sizeof(int) * (conflicts_num + 1));
+				conflicts = xrealloc_vector(conflicts, 2, conflicts_num);
 				conflicts[conflicts_num] = conflicts_package_num;
 				conflicts_num++;
 			}
@@ -1170,7 +1169,8 @@ static char **create_list(const char *filename)
 	file_list = NULL;
 	count = 0;
 	while ((line = xmalloc_fgetline(list_stream)) != NULL) {
-		file_list = xrealloc(file_list, sizeof(char *) * (count + 2));
+//TODO: zeroing xrealloc_vector? 
+		file_list = xrealloc_vector(file_list, 2, count);
 		file_list[count++] = line;
 		file_list[count] = NULL;
 	}
@@ -1634,7 +1634,7 @@ int dpkg_main(int argc UNUSED_PARAM, char **argv)
 	/* Read arguments and store relevant info in structs */
 	while (*argv) {
 		/* deb_count = nb_elem - 1 and we need nb_elem + 1 to allocate terminal node [NULL pointer] */
-		deb_file = xrealloc(deb_file, sizeof(deb_file[0]) * (deb_count + 2));
+		deb_file = xrealloc_vector(deb_file, 2, deb_count);
 		deb_file[deb_count] = xzalloc(sizeof(deb_file[0][0]));
 		if (opt & (OPT_install | OPT_unpack)) {
 			/* -i/-u: require filename */

coreutils/cut.c

@@ -241,9 +241,10 @@ int cut_main(int argc UNUSED_PARAM, char **argv)
 			}
 
 			/* add the new list */
-			cut_lists = xrealloc(cut_lists, sizeof(struct cut_list) * (++nlists));
-			cut_lists[nlists-1].startpos = s;
-			cut_lists[nlists-1].endpos = e;
+			cut_lists = xrealloc_vector(cut_lists, 4, nlists);
+			cut_lists[nlists].startpos = s;
+			cut_lists[nlists].endpos = e;
+			nlists++;
 		}
 
 		/* make sure we got some cut positions out of all that */

coreutils/od_bloaty.c

@@ -735,9 +735,9 @@ decode_format_string(const char *s)
 
 		assert(s != next);
 		s = next;
+		spec = xrealloc_vector(spec, 4, n_specs);
+		memcpy(&spec[n_specs], &tspec, sizeof(spec[0]));
 		n_specs++;
-		spec = xrealloc(spec, n_specs * sizeof(*spec));
-		memcpy(&spec[n_specs-1], &tspec, sizeof *spec);
 	}
 }
 

coreutils/sort.c

@@ -360,8 +360,7 @@ int sort_main(int argc UNUSED_PARAM, char **argv)
 		for (;;) {
 			line = GET_LINE(fp);
 			if (!line) break;
-			if (!(linecount & 63))
-				lines = xrealloc(lines, sizeof(char *) * (linecount + 64));
+			lines = xrealloc_vector(lines, 6, linecount);
 			lines[linecount++] = line;
 		}
 		fclose_if_not_stdin(fp);

debianutils/run_parts.c

@@ -90,7 +90,7 @@ static int FAST_FUNC act(const char *file, struct stat *statbuf, void *args UNUS
 		return SKIP;
 	}
 
-	names = xrealloc(names, (cur + 2) * sizeof(names[0]));
+	names = xrealloc_vector(names, 4, cur);
 	names[cur++] = xstrdup(file);
 	names[cur] = NULL;
 

e2fsprogs/fsck.c

@@ -1028,13 +1028,13 @@ static void parse_args(char **argv)
 // FIXME: must check that arg is a blkdev, or resolve
 // "/path", "UUID=xxx" or "LABEL=xxx" into block device name
 // ("UUID=xxx"/"LABEL=xxx" can probably shifted to fsck.auto duties)
-			devices = xrealloc(devices, (num_devices+1) * sizeof(devices[0]));
+			devices = xrealloc_vector(devices, 2, num_devices);
 			devices[num_devices++] = xstrdup(arg);
 			continue;
 		}
 
 		if (arg[0] != '-' || opts_for_fsck) {
-			args = xrealloc(args, (num_args+1) * sizeof(args[0]));
+			args = xrealloc_vector(args, 2, num_args);
 			args[num_args++] = xstrdup(arg);
 			continue;
 		}
@@ -1111,7 +1111,7 @@ static void parse_args(char **argv)
 		if (optpos) {
 			options[0] = '-';
 			options[optpos + 1] = '\0';
-			args = xrealloc(args, (num_args+1) * sizeof(args[0]));
+			args = xrealloc_vector(args, 2, num_args);
 			args[num_args++] = options;
 		}
 	}

editors/awk.c

@@ -1473,8 +1473,10 @@ static regex_t *as_regex(node *op, regex_t *preg)
 /* gradually increasing buffer */
 static void qrealloc(char **b, int n, int *size)
 {
-	if (!*b || n >= *size)
-		*b = xrealloc(*b, *size = n + (n>>1) + 80);
+	if (!*b || n >= *size) {
+		*size = n + (n>>1) + 80;
+		*b = xrealloc(*b, *size);
+	}
 }
 
 /* resize field storage space */

editors/diff.c

@@ -1059,6 +1059,7 @@ static unsigned diffreg(char *file1, char *file2, int flags)
 
 	member = (int *) nfile[1];
 	equiv(sfile[0], slen[0], sfile[1], slen[1], member);
+//TODO: xrealloc_vector?
 	member = xrealloc(member, (slen[1] + 2) * sizeof(int));
 
 	class = (int *) nfile[0];
@@ -1168,8 +1169,7 @@ static int FAST_FUNC add_to_dirlist(const char *filename,
 		void *userdata,
 		int depth UNUSED_PARAM)
 {
-	/* +2: with space for eventual trailing NULL */
-	dl = xrealloc(dl, (dl_count+2) * sizeof(dl[0]));
+	dl = xrealloc_vector(dl, 5, dl_count);
 	dl[dl_count] = xstrdup(filename + (int)(ptrdiff_t)userdata);
 	dl_count++;
 	return TRUE;

editors/sed.c

@@ -732,8 +732,7 @@ static void flush_append(void)
 
 static void add_input_file(FILE *file)
 {
-	G.input_file_list = xrealloc(G.input_file_list,
-			(G.input_file_count + 1) * sizeof(FILE *));
+	G.input_file_list = xrealloc_vector(G.input_file_list, 2, G.input_file_count);
 	G.input_file_list[G.input_file_count++] = file;
 }
 

include/libbb.h

@@ -564,10 +564,14 @@ void fputc_printable(int ch, FILE *file) FAST_FUNC;
 
 /* dmalloc will redefine these to it's own implementation. It is safe
  * to have the prototypes here unconditionally.  */
-extern void *malloc_or_warn(size_t size) FAST_FUNC;
-extern void *xmalloc(size_t size) FAST_FUNC;
-extern void *xzalloc(size_t size) FAST_FUNC;
-extern void *xrealloc(void *old, size_t size) FAST_FUNC;
+void *malloc_or_warn(size_t size) FAST_FUNC;
+void *xmalloc(size_t size) FAST_FUNC;
+void *xzalloc(size_t size) FAST_FUNC;
+void *xrealloc(void *old, size_t size) FAST_FUNC;
+#define xrealloc_vector(vector, shift, idx) \
+	xrealloc_vector_helper((vector), (sizeof((vector)[0]) << 8) + (shift), (idx))
+void* xrealloc_vector_helper(void *vector, unsigned sizeof_and_shift, int idx) FAST_FUNC;
+
 
 extern ssize_t safe_read(int fd, void *buf, size_t count) FAST_FUNC;
 extern ssize_t nonblock_safe_read(int fd, void *buf, size_t count) FAST_FUNC;

libbb/Kbuild

@@ -109,6 +109,7 @@ lib-y += xfunc_die.o
 lib-y += xgetcwd.o
 lib-y += xgethostbyname.o
 lib-y += xreadlink.o
+lib-y += xrealloc_vector.o
 
 # conditionally compiled objects:
 lib-$(CONFIG_FEATURE_MOUNT_LOOP) += loop.o

libbb/lineedit.c

@@ -400,11 +400,8 @@ static void free_tab_completion_data(void)
 
 static void add_match(char *matched)
 {
-	int nm = num_matches;
-	int nm1 = nm + 1;
-
-	matches = xrealloc(matches, nm1 * sizeof(char *));
-	matches[nm] = matched;
+	matches = xrealloc_vector(matches, 4, num_matches);
+	matches[num_matches] = matched;
 	num_matches++;
 }
 

libbb/mtab.c

@@ -27,14 +27,14 @@ void FAST_FUNC erase_mtab(const char *name)
 	}
 
 	while ((m = getmntent(mountTable)) != 0) {
+		entries = xrealloc(entries, 3, count);
+		entries[count].mnt_fsname = xstrdup(m->mnt_fsname);
+		entries[count].mnt_dir = xstrdup(m->mnt_dir);
+		entries[count].mnt_type = xstrdup(m->mnt_type);
+		entries[count].mnt_opts = xstrdup(m->mnt_opts);
+		entries[count].mnt_freq = m->mnt_freq;
+		entries[count].mnt_passno = m->mnt_passno;
 		i = count++;
-		entries = xrealloc(entries, count * sizeof(entries[0]));
-		entries[i].mnt_fsname = xstrdup(m->mnt_fsname);
-		entries[i].mnt_dir = xstrdup(m->mnt_dir);
-		entries[i].mnt_type = xstrdup(m->mnt_type);
-		entries[i].mnt_opts = xstrdup(m->mnt_opts);
-		entries[i].mnt_freq = m->mnt_freq;
-		entries[i].mnt_passno = m->mnt_passno;
 	}
 	endmntent(mountTable);
 

libbb/procps.c

@@ -45,8 +45,8 @@ static int get_cached(cache_t *cp, unsigned id)
 	for (i = 0; i < cp->size; i++)
 		if (cp->cache[i].id == id)
 			return i;
-	i = cp->size++;
-	cp->cache = xrealloc(cp->cache, cp->size * sizeof(*cp->cache));
+	i = cp->size;
+	cp->cache = xrealloc_vector(cp->cache, 2, cp->size++);
 	cp->cache[i++].id = id;
 	return -i;
 }
@@ -59,8 +59,8 @@ static char* get_cached(cache_t *cp, unsigned id, ug_func* fp)
 	for (i = 0; i < cp->size; i++)
 		if (cp->cache[i].id == id)
 			return cp->cache[i].name;
-	i = cp->size++;
-	cp->cache = xrealloc(cp->cache, cp->size * sizeof(*cp->cache));
+	i = cp->size;
+	cp->cache = xrealloc_vector(cp->cache, 2, cp->size++);
 	cp->cache[i].id = id;
 	/* Never fails. Generates numeric string if name isn't found */
 	fp(cp->cache[i].name, sizeof(cp->cache[i].name), id);

libbb/read.c

@@ -291,3 +291,52 @@ void* FAST_FUNC xmalloc_xopen_read_close(const char *filename, size_t *sizep)
 		bb_perror_msg_and_die("can't read '%s'", filename);
 	return buf;
 }
+
+/* libbb candidate */
+#if 0
+static void *xmalloc_read(int fd, size_t *sizep)
+{
+	char *buf;
+	size_t size, rd_size, total;
+	off_t to_read;
+	struct stat st;
+
+	to_read = sizep ? *sizep : INT_MAX; /* max to read */
+
+	/* Estimate file size */
+	st.st_size = 0; /* in case fstat fails, assume 0 */
+	fstat(fd, &st);
+	/* /proc/N/stat files report st_size 0 */
+	/* In order to make such files readable, we add small const */
+	size = (st.st_size | 0x3ff) + 1;
+
+	total = 0;
+	buf = NULL;
+	while (1) {
+		if (to_read < size)
+			size = to_read;
+		buf = xrealloc(buf, total + size + 1);
+		rd_size = full_read(fd, buf + total, size);
+		if ((ssize_t)rd_size < 0) { /* error */
+			free(buf);
+			return NULL;
+		}
+		total += rd_size;
+		if (rd_size < size) /* EOF */
+			break;
+		to_read -= rd_size;
+		if (to_read <= 0)
+			break;
+		/* grow by 1/8, but in [1k..64k] bounds */
+		size = ((total / 8) | 0x3ff) + 1;
+		if (size > 64*1024)
+			size = 64*1024;
+	}
+	xrealloc(buf, total + 1);
+	buf[total] = '\0';
+
+	if (sizep)
+		*sizep = total;
+	return buf;
+}
+#endif

libpwdgrp/pwd_grp.c

@@ -643,11 +643,7 @@ int initgroups(const char *user, gid_t gid)
 			if (group.gr_gid != gid) {
 				for (m = group.gr_mem; *m; m++) {
 					if (!strcmp(*m, user)) {
-						if (!(num_groups & 7)) {
-							gid_t *tmp = xrealloc(group_list,
-									(num_groups+8) * sizeof(gid_t *));
-							group_list = tmp;
-						}
+						group_list = xrealloc_vector(group_list, 3, num_groups);
 						group_list[num_groups++] = group.gr_gid;
 						break;
 					}

miscutils/less.c

@@ -322,7 +322,7 @@ static void read_lines(void)
 		}
  reached_eof:
 		last_terminated = terminated;
-		flines = xrealloc(flines, (max_fline+1) * sizeof(char *));
+		flines = xrealloc_vector(flines, 8, max_fline);
 		if (option_mask32 & FLAG_N) {
 			/* Width of 7 preserves tab spacing in the text */
 			flines[max_fline] = xasprintf(
@@ -933,7 +933,7 @@ static void fill_match_lines(unsigned pos)
 		/* and we didn't match it last time */
 		 && !(num_matches && match_lines[num_matches-1] == pos)
 		) {
-			match_lines = xrealloc(match_lines, (num_matches+1) * sizeof(int));
+			match_lines = xrealloc_vector(match_lines, 4, num_matches);
 			match_lines[num_matches++] = pos;
 		}
 		pos++;

miscutils/man.c

@@ -117,11 +117,7 @@ int man_main(int argc UNUSED_PARAM, char **argv)
 					count_mp++;
 					/* man_path_list is NULL terminated */
 					man_path_list[count_mp] = NULL;
-					if (!(count_mp & 0xf)) { /* 0x10, 0x20 etc */
-						/* so that last valid man_path_list[] is [count_mp + 0x10] */
-						man_path_list = xrealloc(man_path_list,
-							(count_mp + 0x11) * sizeof(man_path_list[0]));
-					}
+					man_path_list = xrealloc_vector(man_path_list, 4, count_mp);
 				}
 				if (strcmp("MANSECT", line) == 0) {
 					free(sec_list);

modutils/insmod.c

@@ -2201,7 +2201,7 @@ static struct obj_section *obj_create_alloced_section(struct obj_file *f,
 	int newidx = f->header.e_shnum++;
 	struct obj_section *sec;
 
-	f->sections = xrealloc(f->sections, (newidx + 1) * sizeof(sec));
+	f->sections = xrealloc_vector(f->sections, 2, newidx);
 	f->sections[newidx] = sec = arch_new_section();
 
 	sec->header.sh_type = SHT_PROGBITS;
@@ -2250,7 +2250,8 @@ static void *obj_extend_section(struct obj_section *sec, unsigned long more)
 {
 	unsigned long oldsize = sec->header.sh_size;
 	if (more) {
-		sec->contents = xrealloc(sec->contents, sec->header.sh_size += more);
+		sec->header.sh_size += more;
+		sec->contents = xrealloc(sec->contents, sec->header.sh_size);
 	}
 	return sec->contents + oldsize;
 }
@@ -2736,7 +2737,8 @@ static void new_get_kernel_symbols(void)
  retry_kern_sym_load:
 	if (query_module(NULL, QM_SYMBOLS, syms, bufsize, &ret)) {
 		if (errno == ENOSPC && bufsize < ret) {
-			syms = xrealloc(syms, bufsize = ret);
+			bufsize = ret;
+			syms = xrealloc(syms, bufsize);
 			goto retry_kern_sym_load;
 		}
 		bb_perror_msg_and_die("kernel: QM_SYMBOLS");
@@ -3080,7 +3082,7 @@ static void obj_allocate_commons(struct obj_file *f)
 		if (i == f->header.e_shnum) {
 			struct obj_section *sec;
 
-			f->sections = xrealloc(f->sections, (i + 1) * sizeof(sec));
+			f->sections = xrealloc(f->sections, 2, i);
 			f->sections[i] = sec = arch_new_section();
 			f->header.e_shnum = i + 1;
 

modutils/modprobe-small.c

@@ -317,9 +317,7 @@ static FAST_FUNC int fileAction(const char *pathname,
 	}
 
 	cur = module_count++;
-	if (!(cur & 0xfff)) {
-		modinfo = xrealloc(modinfo, sizeof(modinfo[0]) * (cur + 0x1001));
-	}
+	modinfo = xrealloc_vector(modinfo, 12, cur);
 	modinfo[cur].pathname = xstrdup(pathname);
 	modinfo[cur].desc = NULL;
 	modinfo[cur+1].pathname = NULL;

modutils/modprobe.c

@@ -482,10 +482,8 @@ static struct dep_t *build_dep(void)
 				dep = xstrndup(deps, next - deps - ext + 1);
 
 				/* Add the new dependable module name */
-				current->m_depcnt++;
-				current->m_deparr = xrealloc(current->m_deparr,
-						sizeof(char *) * current->m_depcnt);
-				current->m_deparr[current->m_depcnt - 1] = dep;
+				current->m_deparr = xrealloc_vector(current->m_deparr, 2, current->m_depcnt);
+				current->m_deparr[current->m_depcnt++] = dep;
 
 				p = next + 2;
 			} while (next < end);

networking/ifupdown.c

@@ -721,11 +721,7 @@ static struct interfaces_file_t *read_interfaces(const char *filename)
 			currmap = xzalloc(sizeof(*currmap));
 
 			while ((first_word = next_word(&rest_of_line)) != NULL) {
-				if (currmap->n_matches >= currmap->max_matches) {
-					currmap->max_matches = currmap->max_matches * 2 + 1;
-					currmap->match = xrealloc(currmap->match,
-						sizeof(*currmap->match) * currmap->max_matches);
-				}
+				currmap->match = xrealloc_vector(currmap->match, 4, currmap->n_matches);
 				currmap->match[currmap->n_matches++] = xstrdup(first_word);
 			}
 			/*currmap->max_mappings = 0; - done by xzalloc */

procps/ps.c

@@ -303,9 +303,8 @@ static const ps_out_t out_spec[] = {
 
 static ps_out_t* new_out_t(void)
 {
-	int i = out_cnt++;
-	out = xrealloc(out, out_cnt * sizeof(*out));
-	return &out[i];
+	out = xrealloc_vector(out, 2, out_cnt);
+	return &out[out_cnt++];
 }
 
 static const ps_out_t* find_out_spec(const char *name)

procps/top.c

@@ -814,7 +814,7 @@ int top_main(int argc UNUSED_PARAM, char **argv)
 			int n;
 			if (scan_mask == TOP_MASK) {
 				n = ntop;
-				top = xrealloc(top, (++ntop) * sizeof(*top));
+				top = xrealloc_vector(top, 2, ntop++);
 				top[n].pid = p->pid;
 				top[n].ppid = p->ppid;
 				top[n].vsz = p->vsz;
@@ -829,7 +829,8 @@ int top_main(int argc UNUSED_PARAM, char **argv)
 				if (!(p->mapped_ro | p->mapped_rw))
 					continue; /* kernel threads are ignored */
 				n = ntop;
-				top = xrealloc(topmem, (++ntop) * sizeof(*topmem));
+				/* No bug here - top and topmem are the same */
+				top = xrealloc_vector(topmem, 2, ntop++);
 				strcpy(topmem[n].comm, p->comm);
 				topmem[n].pid      = p->pid;
 				topmem[n].vsz      = p->mapped_rw + p->mapped_ro;

util-linux/getopt.c

@@ -238,8 +238,8 @@ static struct option *add_long_options(struct option *long_options, char *option
 				if (tlen == 0)
 					bb_error_msg_and_die("empty long option specified");
 			}
-			long_options = xrealloc(long_options,
-					sizeof(long_options[0]) * (long_nr+2));
+//TODO: zeroing version of xrealloc_vector!
+			long_options = xrealloc_vector(long_options, 4, long_nr);
 			long_options[long_nr].has_arg = arg_opt;
 			long_options[long_nr].flag = NULL;
 			long_options[long_nr].val = LONG_OPT;