perf tools: Update strbuf to remove xrealloc

index 8fb7329..a98bb60 100644
@@ -1,3 +1,4 @@
+#include "debug.h"
 #include "cache.h"
 #include <linux/kernel.h>
 

@@ -17,12 +18,13 @@ int prefixcmp(const char *str, const char *prefix)
  */
 char strbuf_slopbuf[1];
 
-void strbuf_init(struct strbuf *sb, ssize_t hint)
+int strbuf_init(struct strbuf *sb, ssize_t hint)
 {
 	sb->alloc = sb->len = 0;
 	sb->buf = strbuf_slopbuf;
 	if (hint)
-		strbuf_grow(sb, hint);
+		return strbuf_grow(sb, hint);
+	return 0;
 }
 
 void strbuf_release(struct strbuf *sb)

@@ -42,67 +44,104 @@ char *strbuf_detach(struct strbuf *sb, size_t *sz)
 	return res;
 }
 
-void strbuf_grow(struct strbuf *sb, size_t extra)
+int strbuf_grow(struct strbuf *sb, size_t extra)
 {
-	if (sb->len + extra + 1 <= sb->len)
-		die("you want to use way too much memory");
-	if (!sb->alloc)
-		sb->buf = NULL;
-	ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
+	char *buf;
+	size_t nr = sb->len + extra + 1;
+
+	if (nr < sb->alloc)
+		return 0;
+
+	if (nr <= sb->len)
+		return -E2BIG;
+
+	if (alloc_nr(sb->alloc) > nr)
+		nr = alloc_nr(sb->alloc);
+
+	buf = malloc(nr * sizeof(*buf));
+	if (!buf)
+		return -ENOMEM;
+
+	if (sb->alloc) {
+		memcpy(buf, sb->buf, sb->alloc);
+		free(sb->buf);
+	}
+	sb->buf = buf;
+	sb->alloc = nr;
+	return 0;
 }
 
-void strbuf_addch(struct strbuf *sb, int c)
+int strbuf_addch(struct strbuf *sb, int c)
 {
-	strbuf_grow(sb, 1);
+	int ret = strbuf_grow(sb, 1);
+	if (ret)
+		return ret;
+
 	sb->buf[sb->len++] = c;
 	sb->buf[sb->len] = '\0';
+	return 0;
 }
 
-void strbuf_add(struct strbuf *sb, const void *data, size_t len)
+int strbuf_add(struct strbuf *sb, const void *data, size_t len)
 {
-	strbuf_grow(sb, len);
+	int ret = strbuf_grow(sb, len);
+	if (ret)
+		return ret;
+
 	memcpy(sb->buf + sb->len, data, len);
-	strbuf_setlen(sb, sb->len + len);
+	return strbuf_setlen(sb, sb->len + len);
 }
 
-static void strbuf_addv(struct strbuf *sb, const char *fmt, va_list ap)
+static int strbuf_addv(struct strbuf *sb, const char *fmt, va_list ap)
 {
-	int len;
+	int len, ret;
 	va_list ap_saved;
 
-	if (!strbuf_avail(sb))
-		strbuf_grow(sb, 64);
+	if (!strbuf_avail(sb)) {
+		ret = strbuf_grow(sb, 64);
+		if (ret)
+			return ret;
+	}
 
 	va_copy(ap_saved, ap);
 	len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
 	if (len < 0)
-		die("your vsnprintf is broken");
+		return len;
 	if (len > strbuf_avail(sb)) {
-		strbuf_grow(sb, len);
+		ret = strbuf_grow(sb, len);
+		if (ret)
+			return ret;
 		len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap_saved);
 		va_end(ap_saved);
 		if (len > strbuf_avail(sb)) {
-			die("this should not happen, your vsnprintf is broken");
+			pr_debug("this should not happen, your vsnprintf is broken");
+			return -EINVAL;
 		}
 	}
-	strbuf_setlen(sb, sb->len + len);
+	return strbuf_setlen(sb, sb->len + len);
 }
 
-void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
+int strbuf_addf(struct strbuf *sb, const char *fmt, ...)
 {
 	va_list ap;
+	int ret;
 
 	va_start(ap, fmt);
-	strbuf_addv(sb, fmt, ap);
+	ret = strbuf_addv(sb, fmt, ap);
 	va_end(ap);
+	return ret;
 }
 
 ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint)
 {
 	size_t oldlen = sb->len;
 	size_t oldalloc = sb->alloc;
+	int ret;
+
+	ret = strbuf_grow(sb, hint ? hint : 8192);
+	if (ret)
+		return ret;
 
-	strbuf_grow(sb, hint ? hint : 8192);
 	for (;;) {
 		ssize_t cnt;
 

@@ -112,12 +151,14 @@ ssize_t strbuf_read(struct strbuf *sb, int fd, ssize_t hint)
 				strbuf_release(sb);
 			else
 				strbuf_setlen(sb, oldlen);
-			return -1;
+			return cnt;
 		}
 		if (!cnt)
 			break;
 		sb->len += cnt;
-		strbuf_grow(sb, 8192);
+		ret = strbuf_grow(sb, 8192);
+		if (ret)
+			return ret;
 	}
 
 	sb->buf[sb->len] = '\0';

index ab9be0fb..54b4092 100644
@@ -51,7 +51,7 @@ struct strbuf {
 #define STRBUF_INIT  { 0, 0, strbuf_slopbuf }
 
 /*----- strbuf life cycle -----*/
-void strbuf_init(struct strbuf *buf, ssize_t hint);
+int strbuf_init(struct strbuf *buf, ssize_t hint);
 void strbuf_release(struct strbuf *buf);
 char *strbuf_detach(struct strbuf *buf, size_t *);
 

@@ -60,26 +60,31 @@ static inline ssize_t strbuf_avail(const struct strbuf *sb) {
 	return sb->alloc ? sb->alloc - sb->len - 1 : 0;
 }
 
-void strbuf_grow(struct strbuf *buf, size_t);
+int strbuf_grow(struct strbuf *buf, size_t);
 
-static inline void strbuf_setlen(struct strbuf *sb, size_t len) {
-	if (!sb->alloc)
-		strbuf_grow(sb, 0);
+static inline int strbuf_setlen(struct strbuf *sb, size_t len) {
+	int ret;
+	if (!sb->alloc) {
+		ret = strbuf_grow(sb, 0);
+		if (ret)
+			return ret;
+	}
 	assert(len < sb->alloc);
 	sb->len = len;
 	sb->buf[len] = '\0';
+	return 0;
 }
 
 /*----- add data in your buffer -----*/
-void strbuf_addch(struct strbuf *sb, int c);
+int strbuf_addch(struct strbuf *sb, int c);
 
-void strbuf_add(struct strbuf *buf, const void *, size_t);
-static inline void strbuf_addstr(struct strbuf *sb, const char *s) {
-	strbuf_add(sb, s, strlen(s));
+int strbuf_add(struct strbuf *buf, const void *, size_t);
+static inline int strbuf_addstr(struct strbuf *sb, const char *s) {
+	return strbuf_add(sb, s, strlen(s));
 }
 
 __attribute__((format(printf,2,3)))
-void strbuf_addf(struct strbuf *sb, const char *fmt, ...);
+int strbuf_addf(struct strbuf *sb, const char *fmt, ...);
 
 /* XXX: if read fails, any partial read is undone */
 ssize_t strbuf_read(struct strbuf *, int fd, ssize_t hint);

index aea189b..8c8b4c1 100644
@@ -915,8 +915,7 @@ int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
 		tmp = "*";
 	else if (tag == DW_TAG_subroutine_type) {
 		/* Function pointer */
-		strbuf_add(buf, "(function_type)", 15);
-		return 0;
+		return strbuf_add(buf, "(function_type)", 15);
 	} else {
 		if (!dwarf_diename(&type))
 			return -ENOENT;

@@ -927,14 +926,10 @@ int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
 		else if (tag == DW_TAG_enumeration_type)
 			tmp = "enum ";
 		/* Write a base name */
-		strbuf_addf(buf, "%s%s", tmp, dwarf_diename(&type));
-		return 0;
+		return strbuf_addf(buf, "%s%s", tmp, dwarf_diename(&type));
 	}
 	ret = die_get_typename(&type, buf);
-	if (ret == 0)
-		strbuf_addstr(buf, tmp);
-
-	return ret;
+	return ret ? ret : strbuf_addstr(buf, tmp);
 }
 
 /**

@@ -951,12 +946,10 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
 	ret = die_get_typename(vr_die, buf);
 	if (ret < 0) {
 		pr_debug("Failed to get type, make it unknown.\n");
-		strbuf_add(buf, " (unknown_type)", 14);
+		ret = strbuf_add(buf, " (unknown_type)", 14);
 	}
 
-	strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
-
-	return 0;
+	return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
 }
 
 #ifdef HAVE_DWARF_GETLOCATIONS

@@ -998,23 +991,23 @@ static int die_get_var_innermost_scope(Dwarf_Die *sp_die, Dwarf_Die *vr_die,
 		goto out;
 	}
 
-	while ((offset = dwarf_ranges(&scopes[1], offset, &base,
-				&start, &end)) > 0) {
+	while (!ret && (offset = dwarf_ranges(&scopes[1], offset, &base,
+					&start, &end)) > 0) {
 		start -= entry;
 		end -= entry;
 
 		if (first) {
-			strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
-				name, start, end);
+			ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
+					  name, start, end);
 			first = false;
 		} else {
-			strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
-				start, end);
+			ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
+					  start, end);
 		}
 	}
 
-	if (!first)
-		strbuf_add(buf, "]>", 2);
+	if (!ret && !first)
+		ret = strbuf_add(buf, "]>", 2);
 
 out:
 	free(scopes);

@@ -1054,9 +1047,8 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
 	if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
 		return -EINVAL;
 
-	while ((offset = dwarf_getlocations(
-				&attr, offset, &base,
-				&start, &end, &op, &nops)) > 0) {
+	while (!ret && (offset = dwarf_getlocations(&attr, offset, &base,
+					&start, &end, &op, &nops)) > 0) {
 		if (start == 0) {
 			/* Single Location Descriptions */
 			ret = die_get_var_innermost_scope(sp_die, vr_die, buf);

@@ -1067,17 +1059,17 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
 		start -= entry;
 		end -= entry;
 		if (first) {
-			strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
-				name, start, end);
+			ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
+					  name, start, end);
 			first = false;
 		} else {
-			strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
-				start, end);
+			ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
+					  start, end);
 		}
 	}
 
-	if (!first)
-		strbuf_add(buf, "]>", 2);
+	if (!ret && !first)
+		ret = strbuf_add(buf, "]>", 2);
 
 	return ret;
 }

312 lines not on this page · raw message

index 9f68875..1259839 100644
@@ -1294,6 +1294,7 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 {
 	struct available_var_finder *af = data;
 	struct variable_list *vl;
+	struct strbuf buf = STRBUF_INIT;
 	int tag, ret;
 
 	vl = &af->vls[af->nvls - 1];

@@ -1307,25 +1308,26 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 		if (ret == 0 || ret == -ERANGE) {
 			int ret2;
 			bool externs = !af->child;
-			struct strbuf buf;
 
-			strbuf_init(&buf, 64);
+			if (strbuf_init(&buf, 64) < 0)
+				goto error;
 
 			if (probe_conf.show_location_range) {
-				if (!externs) {
-					if (ret)
-						strbuf_add(&buf, "[INV]\t", 6);
-					else
-						strbuf_add(&buf, "[VAL]\t", 6);
-				} else
-					strbuf_add(&buf, "[EXT]\t", 6);
+				if (!externs)
+					ret2 = strbuf_add(&buf,
+						ret ? "[INV]\t" : "[VAL]\t", 6);
+				else
+					ret2 = strbuf_add(&buf, "[EXT]\t", 6);
+				if (ret2)
+					goto error;
 			}
 
 			ret2 = die_get_varname(die_mem, &buf);
 
 			if (!ret2 && probe_conf.show_location_range &&
 				!externs) {
-				strbuf_addch(&buf, '\t');
+				if (strbuf_addch(&buf, '\t') < 0)
+					goto error;
 				ret2 = die_get_var_range(&af->pf.sp_die,
 							die_mem, &buf);
 			}

@@ -1334,8 +1336,8 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 			if (ret2 == 0) {
 				strlist__add(vl->vars,
 					strbuf_detach(&buf, NULL));
-			} else
-				strbuf_release(&buf);
+			}
+			strbuf_release(&buf);
 		}
 	}
 

@@ -1343,6 +1345,10 @@ static int collect_variables_cb(Dwarf_Die *die_mem, void *data)
 		return DIE_FIND_CB_CONTINUE;
 	else
 		return DIE_FIND_CB_SIBLING;
+error:
+	strbuf_release(&buf);
+	pr_debug("Error in strbuf\n");
+	return DIE_FIND_CB_END;
 }
 
 /* Add a found vars into available variables list */

index bc1de9b..f9830c9 100644
@@ -61,6 +61,7 @@ static int check_emacsclient_version(void)
 	struct child_process ec_process;
 	const char *argv_ec[] = { "emacsclient", "--version", NULL };
 	int version;
+	int ret = -1;
 
 	/* emacsclient prints its version number on stderr */
 	memset(&ec_process, 0, sizeof(ec_process));

@@ -71,7 +72,10 @@ static int check_emacsclient_version(void)
 		fprintf(stderr, "Failed to start emacsclient.\n");
 		return -1;
 	}
-	strbuf_read(&buffer, ec_process.err, 20);
+	if (strbuf_read(&buffer, ec_process.err, 20) < 0) {
+		fprintf(stderr, "Failed to read emacsclient version\n");
+		goto out;
+	}
 	close(ec_process.err);
 
 	/*

@@ -82,8 +86,7 @@ static int check_emacsclient_version(void)
 
 	if (prefixcmp(buffer.buf, "emacsclient")) {
 		fprintf(stderr, "Failed to parse emacsclient version.\n");
-		strbuf_release(&buffer);
-		return -1;
+		goto out;
 	}
 
 	version = atoi(buffer.buf + strlen("emacsclient"));

@@ -92,12 +95,11 @@ static int check_emacsclient_version(void)
 		fprintf(stderr,
 			"emacsclient version '%d' too old (< 22).\n",
 			version);
-		strbuf_release(&buffer);
-		return -1;
-	}
-
+	} else
+		ret = 0;
+out:
 	strbuf_release(&buffer);
-	return 0;
+	return ret;
 }
 
 static void exec_woman_emacs(const char *path, const char *page)

index 83ffe7c..7970008 100644
@@ -309,9 +309,11 @@ static int handle_alias(int *argcp, const char ***argv)
 			if (*argcp > 1) {
 				struct strbuf buf;
 
-				strbuf_init(&buf, PATH_MAX);
-				strbuf_addstr(&buf, alias_string);
-				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
+				if (strbuf_init(&buf, PATH_MAX) < 0 ||
+				    strbuf_addstr(&buf, alias_string) < 0 ||
+				    sq_quote_argv(&buf, (*argv) + 1,
+						  PATH_MAX) < 0)
+					die("Failed to allocate memory.");
 				free(alias_string);
 				alias_string = buf.buf;
 			}

index 01f0324..c6d4ee2 100644
@@ -17,38 +17,42 @@ static inline int need_bs_quote(char c)
 	return (c == '\'' || c == '!');
 }
 
-static void sq_quote_buf(struct strbuf *dst, const char *src)
+static int sq_quote_buf(struct strbuf *dst, const char *src)
 {
 	char *to_free = NULL;
+	int ret;
 
 	if (dst->buf == src)
 		to_free = strbuf_detach(dst, NULL);
 
-	strbuf_addch(dst, '\'');
-	while (*src) {
+	ret = strbuf_addch(dst, '\'');
+	while (!ret && *src) {
 		size_t len = strcspn(src, "'!");
-		strbuf_add(dst, src, len);
+		ret = strbuf_add(dst, src, len);
 		src += len;
-		while (need_bs_quote(*src)) {
-			strbuf_addstr(dst, "'\\");
-			strbuf_addch(dst, *src++);
-			strbuf_addch(dst, '\'');
-		}
+		while (!ret && need_bs_quote(*src))
+			ret = strbuf_addf(dst, "'\\%c\'", *src++);
 	}
-	strbuf_addch(dst, '\'');
+	if (!ret)
+		ret = strbuf_addch(dst, '\'');
 	free(to_free);
+
+	return ret;
 }
 
-void sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
+int sq_quote_argv(struct strbuf *dst, const char** argv, size_t maxlen)
 {
-	int i;
+	int i, ret;
 
 	/* Copy into destination buffer. */
-	strbuf_grow(dst, 255);
-	for (i = 0; argv[i]; ++i) {
-		strbuf_addch(dst, ' ');
-		sq_quote_buf(dst, argv[i]);
+	ret = strbuf_grow(dst, 255);
+	for (i = 0; !ret && argv[i]; ++i) {
+		ret = strbuf_addch(dst, ' ');
+		if (ret)
+			break;
+		ret = sq_quote_buf(dst, argv[i]);
 		if (maxlen && dst->len > maxlen)
 			die("Too many or long arguments");
 	}
+	return ret;
 }

index 3340c9c..e1ec191 100644
@@ -24,6 +24,6 @@
  * sq_quote() in a real application.
  */
 
-void sq_quote_argv(struct strbuf *, const char **argv, size_t maxlen);
+int sq_quote_argv(struct strbuf *, const char **argv, size_t maxlen);
 
 #endif /* __PERF_QUOTE_H */

index 90680ec..5ab74e4 100644
@@ -1819,7 +1819,8 @@ static int process_cpu_topology(struct perf_file_section *section,
 
 	ph->env.nr_sibling_cores = nr;
 	size += sizeof(u32);
-	strbuf_init(&sb, 128);
+	if (strbuf_init(&sb, 128) < 0)
+		goto free_cpu;
 
 	for (i = 0; i < nr; i++) {
 		str = do_read_string(fd, ph);

@@ -1827,7 +1828,8 @@ static int process_cpu_topology(struct perf_file_section *section,
 			goto error;
 
 		/* include a NULL character at the end */
-		strbuf_add(&sb, str, strlen(str) + 1);
+		if (strbuf_add(&sb, str, strlen(str) + 1) < 0)
+			goto error;
 		size += string_size(str);
 		free(str);
 	}

@@ -1849,7 +1851,8 @@ static int process_cpu_topology(struct perf_file_section *section,
 			goto error;
 
 		/* include a NULL character at the end */
-		strbuf_add(&sb, str, strlen(str) + 1);
+		if (strbuf_add(&sb, str, strlen(str) + 1) < 0)
+			goto error;
 		size += string_size(str);
 		free(str);
 	}

@@ -1907,7 +1910,7 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
 	u32 nr, node, i;
 	char *str;
 	uint64_t mem_total, mem_free;
-	struct strbuf sb;
+	struct strbuf sb = STRBUF_INIT;
 
 	/* nr nodes */
 	ret = readn(fd, &nr, sizeof(nr));

@@ -1918,7 +1921,8 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
 		nr = bswap_32(nr);
 
 	ph->env.nr_numa_nodes = nr;
-	strbuf_init(&sb, 256);
+	if (strbuf_init(&sb, 256) < 0)
+		goto error;
 
 	for (i = 0; i < nr; i++) {
 		/* node number */

@@ -1940,15 +1944,17 @@ static int process_numa_topology(struct perf_file_section *section __maybe_unuse
 			mem_free = bswap_64(mem_free);
 		}
 
-		strbuf_addf(&sb, "%u:%"PRIu64":%"PRIu64":",
-			    node, mem_total, mem_free);
+		if (strbuf_addf(&sb, "%u:%"PRIu64":%"PRIu64":",
+				node, mem_total, mem_free) < 0)
+			goto error;
 
 		str = do_read_string(fd, ph);
 		if (!str)
 			goto error;
 
 		/* include a NULL character at the end */
-		strbuf_add(&sb, str, strlen(str) + 1);
+		if (strbuf_add(&sb, str, strlen(str) + 1) < 0)
+			goto error;
 		free(str);
 	}
 	ph->env.numa_nodes = strbuf_detach(&sb, NULL);

@@ -1982,7 +1988,8 @@ static int process_pmu_mappings(struct perf_file_section *section __maybe_unused
 	}
 
 	ph->env.nr_pmu_mappings = pmu_num;
-	strbuf_init(&sb, 128);
+	if (strbuf_init(&sb, 128) < 0)
+		return -1;
 
 	while (pmu_num) {
 		if (readn(fd, &type, sizeof(type)) != sizeof(type))

@@ -1994,9 +2001,11 @@ static int process_pmu_mappings(struct perf_file_section *section __maybe_unused
 		if (!name)
 			goto error;
 
-		strbuf_addf(&sb, "%u:%s", type, name);
+		if (strbuf_addf(&sb, "%u:%s", type, name) < 0)
+			goto error;
 		/* include a NULL character at the end */
-		strbuf_add(&sb, "", 1);
+		if (strbuf_add(&sb, "", 1) < 0)
+			goto error;
 
 		if (!strcmp(name, "msr"))
 			ph->env.msr_pmu_type = type;

index bf34468..ddb0261 100644
@@ -643,20 +643,20 @@ static int pmu_resolve_param_term(struct parse_events_term *term,
 static char *pmu_formats_string(struct list_head *formats)
 {
 	struct perf_pmu_format *format;
-	char *str;
-	struct strbuf buf;
+	char *str = NULL;
+	struct strbuf buf = STRBUF_INIT;
 	unsigned i = 0;
 
 	if (!formats)
 		return NULL;
 
-	strbuf_init(&buf, 0);
 	/* sysfs exported terms */
 	list_for_each_entry(format, formats, list)
-		strbuf_addf(&buf, i++ ? ",%s" : "%s",
-			    format->name);
+		if (strbuf_addf(&buf, i++ ? ",%s" : "%s", format->name) < 0)
+			goto error;
 
 	str = strbuf_detach(&buf, NULL);
+error:
 	strbuf_release(&buf);
 
 	return str;

index 43a98a4..d62ccae 100644
@@ -27,16 +27,27 @@ static int levenshtein_compare(const void *p1, const void *p2)
 	return l1 != l2 ? l1 - l2 : strcmp(s1, s2);
 }
 
-static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
+static int add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
 {
-	unsigned int i;
-
-	ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);
-
+	unsigned int i, nr = cmds->cnt + old->cnt;
+	void *tmp;
+
+	if (nr > cmds->alloc) {
+		/* Choose bigger one to alloc */
+		if (alloc_nr(cmds->alloc) < nr)
+			cmds->alloc = nr;
+		else
+			cmds->alloc = alloc_nr(cmds->alloc);
+		tmp = realloc(cmds->names, cmds->alloc * sizeof(*cmds->names));
+		if (!tmp)
+			return -1;
+		cmds->names = tmp;
+	}
 	for (i = 0; i < old->cnt; i++)
 		cmds->names[cmds->cnt++] = old->names[i];
 	zfree(&old->names);
 	old->cnt = 0;
+	return 0;
 }
 
 const char *help_unknown_cmd(const char *cmd)

@@ -52,8 +63,11 @@ const char *help_unknown_cmd(const char *cmd)
 
 	load_command_list("perf-", &main_cmds, &other_cmds);
 
-	add_cmd_list(&main_cmds, &aliases);
-	add_cmd_list(&main_cmds, &other_cmds);
+	if (add_cmd_list(&main_cmds, &aliases) < 0 ||
+	    add_cmd_list(&main_cmds, &other_cmds) < 0) {
+		fprintf(stderr, "ERROR: Failed to allocate command list for unknown command.\n");
+		goto end;
+	}
 	qsort(main_cmds.names, main_cmds.cnt,
 	      sizeof(main_cmds.names), cmdname_compare);
 	uniq(&main_cmds);

@@ -99,6 +113,6 @@ const char *help_unknown_cmd(const char *cmd)
 		for (i = 0; i < n; i++)
 			fprintf(stderr, "\t%s\n", main_cmds.names[i]->name);
 	}
-
+end:
 	exit(1);
 }

index 1f5a93c..0d814bb 100644
@@ -40,25 +40,6 @@ int split_cmdline(char *cmdline, const char ***argv);
 
 #define alloc_nr(x) (((x)+16)*3/2)
 
-/*
- * Realloc the buffer pointed at by variable 'x' so that it can hold
- * at least 'nr' entries; the number of entries currently allocated
- * is 'alloc', using the standard growing factor alloc_nr() macro.
- *
- * DO NOT USE any expression with side-effect for 'x' or 'alloc'.
- */
-#define ALLOC_GROW(x, nr, alloc) \
-	do { \
-		if ((nr) > alloc) { \
-			if (alloc_nr(alloc) < (nr)) \
-				alloc = (nr); \
-			else \
-				alloc = alloc_nr(alloc); \
-			x = xrealloc((x), alloc * sizeof(*(x))); \
-		} \
-	} while(0)
-
-
 static inline int is_absolute_path(const char *path)
 {
 	return path[0] == '/';

index 88f607a..7651633 100644
@@ -160,12 +160,6 @@ static inline char *gitstrchrnul(const char *s, int c)
 }
 #endif
 
-/*
- * Wrappers:
- */
-void *xrealloc(void *ptr, size_t size) __attribute__((weak));
-
-
 static inline void *zalloc(size_t size)
 {
 	return calloc(1, size);

deleted file mode 100644
index 5f1a07c..0000000
@@ -1,29 +0,0 @@
-/*
- * Various trivial helper wrappers around standard functions
- */
-#include "cache.h"
-
-/*
- * There's no pack memory to release - but stay close to the Git
- * version so wrap this away:
- */
-static inline void release_pack_memory(size_t size __maybe_unused,
-				       int flag __maybe_unused)
-{
-}
-
-void *xrealloc(void *ptr, size_t size)
-{
-	void *ret = realloc(ptr, size);
-	if (!ret && !size)
-		ret = realloc(ptr, 1);
-	if (!ret) {
-		release_pack_memory(size, -1);
-		ret = realloc(ptr, size);
-		if (!ret && !size)
-			ret = realloc(ptr, 1);
-		if (!ret)
-			die("Out of memory, realloc failed");
-	}
-	return ret;
-}