3 files changed, 128 insertions, 0 deletions
diff --git a/src/cmd/Makefile b/src/cmd/Makefile
index 0cde3ff..7c51ebf 100644
--- a/src/cmd/Makefile
+++ b/src/cmd/Makefile
@@ -22,6 +22,8 @@ all:
 		LIBC_DIR=$(shell pwd)/../$(LIBC_DIR)
 	cd cat/; make LDSCRIPT=$(LDSCRIPT) CC=$(CC) AS=$(AS) LD=$(LD) SYSROOT=$(SYSROOT) \
 		LIBC_DIR=$(shell pwd)/../$(LIBC_DIR)
+	cd mex/; make LDSCRIPT=$(LDSCRIPT) CC=$(CC) AS=$(AS) LD=$(LD) SYSROOT=$(SYSROOT) \
+		LIBC_DIR=$(shell pwd)/../$(LIBC_DIR)
 
 .PHONY: clean
 clean:
@@ -33,3 +35,4 @@ clean:
 	cd login/; make clean
 	cd echo/; make clean
 	cd cat/; make clean
+	cd mex/; make clean
diff --git a/src/cmd/mex/Makefile b/src/cmd/mex/Makefile
new file mode 100644
index 0000000..bc88287
--- /dev/null
+++ b/src/cmd/mex/Makefile
@@ -0,0 +1,18 @@
+include ../../data/build/user.mk
+
+CFILES = $(shell find . -name "*.c")
+CFILES = $(shell find . -name "*.c")
+CFLAGS = -L$(LIBC_DIR) -lc $(INTERNAL_CFLAGS) \
+		 -L../../lib/libwidget -lwidget -L../../lib/libc/ -lc \
+		 -I../../lib/libwidget/include/
+OBJECTS = $(CFILES:%.c=%.o)
+
+$(SYSROOT)/usr/bin/mex: $(OBJECTS)
+	$(LD) $(OBJECTS) -o $@ $(CFLAGS)
+
+%.o: %.c
+	$(CC) $(INTERNAL_CFLAGS) -c $(CFLAGS) $< -o $@
+
+.PHONY: clean
+clean:
+	rm -f *.o *.d
diff --git a/src/cmd/mex/mex.c b/src/cmd/mex/mex.c
new file mode 100644
index 0000000..da501c3
--- /dev/null
+++ b/src/cmd/mex/mex.c
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2025 Ian Marco Moffett and L5 engineers
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the project nor the names of its
+ *    contributors may be used to endorse or promote products derived from
+ *    this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <unistd.h>
+#include <stddef.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdarg.h>
+
+#define LINE_LEN 16
+
+static void
+dump_line(const char *line, size_t len)
+{
+    /* The amount of bytes we write */
+    const uint8_t BYTE_COUNT = 2;
+
+    for (size_t i = 0; i < LINE_LEN; ++i) {
+        if (i < len) {
+            printf("%02x", line[i] & 0xFF);
+        } else {
+            printf("  ");
+        }
+
+        /* Put spacing between bytes */
+        if (((i + 1) % BYTE_COUNT) == 0) {
+            printf(" ");
+        }
+    }
+
+    printf(" ");
+    for (size_t i = 0; i < len; ++i) {
+        if (line[i] > 31 && line[i] < 127) {
+            printf("%c", line[i]);
+        } else {
+            printf(".");
+        }
+    }
+
+    printf("\n");
+}
+
+static void
+dump_file(int fd)
+{
+    char buf[LINE_LEN];
+    ssize_t count;
+    size_t offset = 0;
+
+    for (;;) {
+        count = read(fd, buf, sizeof(char) * LINE_LEN);
+        if (count <= 0) {
+            break;
+        }
+
+        printf("%08x: ", offset);
+        offset += LINE_LEN;
+        dump_line(buf, count);
+    }
+}
+
+int
+main(int argc, char **argv)
+{
+    int fd;
+
+    if (__argc < 2) {
+        printf("mex: usage: mex <filename>\n");
+        return -1;
+    }
+
+    if ((fd = open(__argv[1], O_RDONLY)) < 0) {
+        printf("mex: failed to open input\n");
+        return fd;
+    }
+
+    dump_file(fd);
+    close(fd);
+    return 0;
+}