[RFC v7 18/21] um: host: add utilities functions

[Hajime Tazaki]

Add basic utility functions for getting a string from a kernel error
code and a fprintf like function that uses the host print
operation. The latter is useful for informing the user about errors
that occur in the host library.

Signed-off-by: Hajime Tazaki <thehajime at gmail.com>
---
 tools/um/lib/Build     |   4 +
 tools/um/lib/jmp_buf.c |  14 +++
 tools/um/lib/jmp_buf.h |   8 ++
 tools/um/lib/utils.c   | 210 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 236 insertions(+)
 create mode 100644 tools/um/lib/Build
 create mode 100644 tools/um/lib/jmp_buf.c
 create mode 100644 tools/um/lib/jmp_buf.h
 create mode 100644 tools/um/lib/utils.c

diff --git a/tools/um/lib/Build b/tools/um/lib/Build
new file mode 100644
index 000000000000..fc967af4104a
--- /dev/null
+++ b/tools/um/lib/Build
@@ -0,0 +1,4 @@
+include $(objtree)/include/config/auto.conf
+
+liblinux-$(CONFIG_UMMODE_LIB) += utils.o
+liblinux-$(CONFIG_UMMODE_LIB) += jmp_buf.o
diff --git a/tools/um/lib/jmp_buf.c b/tools/um/lib/jmp_buf.c
new file mode 100644
index 000000000000..f6bdd7e4bd83
--- /dev/null
+++ b/tools/um/lib/jmp_buf.c
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <setjmp.h>
+#include <lkl_host.h>
+
+void jmp_buf_set(struct lkl_jmp_buf *jmpb, void (*f)(void))
+{
+	if (!setjmp(*((jmp_buf *)jmpb->buf)))
+		f();
+}
+
+void jmp_buf_longjmp(struct lkl_jmp_buf *jmpb, int val)
+{
+	longjmp(*((jmp_buf *)jmpb->buf), val);
+}
diff --git a/tools/um/lib/jmp_buf.h b/tools/um/lib/jmp_buf.h
new file mode 100644
index 000000000000..8782cbaaf51f
--- /dev/null
+++ b/tools/um/lib/jmp_buf.h
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LKL_LIB_JMP_BUF_H
+#define _LKL_LIB_JMP_BUF_H
+
+void jmp_buf_set(struct lkl_jmp_buf *jmpb, void (*f)(void));
+void jmp_buf_longjmp(struct lkl_jmp_buf *jmpb, int val);
+
+#endif
diff --git a/tools/um/lib/utils.c b/tools/um/lib/utils.c
new file mode 100644
index 000000000000..4930479a8a35
--- /dev/null
+++ b/tools/um/lib/utils.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+#include <lkl_host.h>
+
+static const char * const lkl_err_strings[] = {
+	"Success",
+	"Operation not permitted",
+	"No such file or directory",
+	"No such process",
+	"Interrupted system call",
+	"I/O error",
+	"No such device or address",
+	"Argument list too long",
+	"Exec format error",
+	"Bad file number",
+	"No child processes",
+	"Try again",
+	"Out of memory",
+	"Permission denied",
+	"Bad address",
+	"Block device required",
+	"Device or resource busy",
+	"File exists",
+	"Cross-device link",
+	"No such device",
+	"Not a directory",
+	"Is a directory",
+	"Invalid argument",
+	"File table overflow",
+	"Too many open files",
+	"Not a typewriter",
+	"Text file busy",
+	"File too large",
+	"No space left on device",
+	"Illegal seek",
+	"Read-only file system",
+	"Too many links",
+	"Broken pipe",
+	"Math argument out of domain of func",
+	"Math result not representable",
+	"Resource deadlock would occur",
+	"File name too long",
+	"No record locks available",
+	"Invalid system call number",
+	"Directory not empty",
+	"Too many symbolic links encountered",
+	"Bad error code", /* EWOULDBLOCK is EAGAIN */
+	"No message of desired type",
+	"Identifier removed",
+	"Channel number out of range",
+	"Level 2 not synchronized",
+	"Level 3 halted",
+	"Level 3 reset",
+	"Link number out of range",
+	"Protocol driver not attached",
+	"No CSI structure available",
+	"Level 2 halted",
+	"Invalid exchange",
+	"Invalid request descriptor",
+	"Exchange full",
+	"No anode",
+	"Invalid request code",
+	"Invalid slot",
+	"Bad error code", /* EDEADLOCK is EDEADLK */
+	"Bad font file format",
+	"Device not a stream",
+	"No data available",
+	"Timer expired",
+	"Out of streams resources",
+	"Machine is not on the network",
+	"Package not installed",
+	"Object is remote",
+	"Link has been severed",
+	"Advertise error",
+	"Srmount error",
+	"Communication error on send",
+	"Protocol error",
+	"Multihop attempted",
+	"RFS specific error",
+	"Not a data message",
+	"Value too large for defined data type",
+	"Name not unique on network",
+	"File descriptor in bad state",
+	"Remote address changed",
+	"Can not access a needed shared library",
+	"Accessing a corrupted shared library",
+	".lib section in a.out corrupted",
+	"Attempting to link in too many shared libraries",
+	"Cannot exec a shared library directly",
+	"Illegal byte sequence",
+	"Interrupted system call should be restarted",
+	"Streams pipe error",
+	"Too many users",
+	"Socket operation on non-socket",
+	"Destination address required",
+	"Message too long",
+	"Protocol wrong type for socket",
+	"Protocol not available",
+	"Protocol not supported",
+	"Socket type not supported",
+	"Operation not supported on transport endpoint",
+	"Protocol family not supported",
+	"Address family not supported by protocol",
+	"Address already in use",
+	"Cannot assign requested address",
+	"Network is down",
+	"Network is unreachable",
+	"Network dropped connection because of reset",
+	"Software caused connection abort",
+	"Connection reset by peer",
+	"No buffer space available",
+	"Transport endpoint is already connected",
+	"Transport endpoint is not connected",
+	"Cannot send after transport endpoint shutdown",
+	"Too many references: cannot splice",
+	"Connection timed out",
+	"Connection refused",
+	"Host is down",
+	"No route to host",
+	"Operation already in progress",
+	"Operation now in progress",
+	"Stale file handle",
+	"Structure needs cleaning",
+	"Not a XENIX named type file",
+	"No XENIX semaphores available",
+	"Is a named type file",
+	"Remote I/O error",
+	"Quota exceeded",
+	"No medium found",
+	"Wrong medium type",
+	"Operation Canceled",
+	"Required key not available",
+	"Key has expired",
+	"Key has been revoked",
+	"Key was rejected by service",
+	"Owner died",
+	"State not recoverable",
+	"Operation not possible due to RF-kill",
+	"Memory page has hardware error",
+};
+
+const char *lkl_strerror(int err)
+{
+	if (err < 0)
+		err = -err;
+
+	if ((size_t)err >= sizeof(lkl_err_strings) / sizeof(const char *))
+		return "Bad error code";
+
+	return lkl_err_strings[err];
+}
+
+void lkl_perror(char *msg, int err)
+{
+	const char *err_msg = lkl_strerror(err);
+	/* We need to use 'real' printf because lkl_host_ops.print can
+	 * be turned off when debugging is off.
+	 */
+	lkl_printf("%s: %s\n", msg, err_msg);
+}
+
+static int lkl_vprintf(const char *fmt, va_list args)
+{
+	int n;
+	char *buffer;
+	va_list copy;
+
+	if (!lkl_host_ops.print)
+		return 0;
+
+	va_copy(copy, args);
+	n = vsnprintf(NULL, 0, fmt, copy);
+	va_end(copy);
+
+	buffer = lkl_host_ops.mem_alloc(n + 1);
+	if (!buffer)
+		return (-1);
+
+	vsnprintf(buffer, n + 1, fmt, args);
+
+	lkl_host_ops.print(buffer, n);
+	lkl_host_ops.mem_free(buffer);
+
+	return n;
+}
+
+int lkl_printf(const char *fmt, ...)
+{
+	int n;
+	va_list args;
+
+	va_start(args, fmt);
+	n = lkl_vprintf(fmt, args);
+	va_end(args);
+
+	return n;
+}
+
+void lkl_bug(const char *fmt, ...)
+{
+	va_list args;
+
+	va_start(args, fmt);
+	lkl_vprintf(fmt, args);
+	va_end(args);
+
+	lkl_host_ops.panic();
+}
-- 
2.21.0 (Apple Git-122.2)