From: Ahmad Fatoum <a.fatoum@pengutronix.de>
Date: Tue, 15 Feb 2022 14:21:47 +0100
Subject: [PATCH] scripts: implement slurp, a read_file with fd as argument

This is useful for host/target tools that use stdin as a fall back to
read from when no file name is supplied.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Upstream-Status: Submitted [https://lore.kernel.org/all/20250411074045.2019372-1-a.fatoum@pengutronix.de/]
---
 scripts/common.c | 29 +++++++++++++++++++++++++++++
 scripts/common.h |  1 +
 2 files changed, 30 insertions(+)

diff --git a/scripts/common.c b/scripts/common.c
index 49c468a1ea35..5d47efd197f9 100644
--- a/scripts/common.c
+++ b/scripts/common.c
@@ -97,6 +97,35 @@ void *read_file(const char *filename, size_t *size)
 	return NULL;
 }
 
+void *slurp(int fd, size_t *size)
+{
+	size_t buflen = 1024;
+	ssize_t readlen = 0;
+	void *buf, *tmp;
+
+	buf = malloc(buflen);
+	if (!buf)
+		return NULL;
+
+	while (1) {
+		readlen = read_full(fd, buf + readlen, 1024);
+		if (readlen < 0)
+			return NULL;
+		*size += readlen;
+		if (readlen != 1024)
+			return buf;
+
+		buflen += 1024;
+		tmp = realloc(buf, buflen);
+		if (!tmp) {
+			free(buf);
+			return NULL;
+		}
+		buf = tmp;
+	}
+
+}
+
 int write_file(const char *filename, const void *buf, size_t size)
 {
 	int fd, ret = 0;
diff --git a/scripts/common.h b/scripts/common.h
index 399729c338f3..4ee1278c6276 100644
--- a/scripts/common.h
+++ b/scripts/common.h
@@ -3,6 +3,7 @@
 
 int read_file_2(const char *filename, size_t *size, void **outbuf, size_t max_size);
 void *read_file(const char *filename, size_t *size);
+void *slurp(int fd, size_t *size);
 int write_file(const char *filename, const void *buf, size_t size);
 int read_full(int fd, void *buf, size_t size);
 int write_full(int fd, const void *buf, size_t size);