usr.bin: Add 'mex' port

See https://osmora.org/cgit/mex

Signed-off-by: Ian Moffett <ian@osmora.org>

3 files changed, 112 insertions, 0 deletions

diff --git a/usr.bin/Makefile b/usr.bin/Makefile
index 80eafc7..779aacd 100644
--- a/usr.bin/Makefile
+++ b/usr.bin/Makefile
@@ -10,3 +10,4 @@ all:
 	make -C fetch/ $(ARGS)
 	make -C kfgwm/ $(ARGS)
 	make -C time/ $(ARGS)
+	make -C mex/ $(ARGS)
diff --git a/usr.bin/mex/Makefile b/usr.bin/mex/Makefile
new file mode 100644
index 0000000..6c0db59
--- /dev/null
+++ b/usr.bin/mex/Makefile
@@ -0,0 +1,6 @@
+include user.mk
+
+CFILES = $(shell find . -name "*.c")
+
+$(ROOT)/base/usr/bin/mex:
+	gcc $(CFILES) -o $@ $(INTERNAL_CFLAGS)
diff --git a/usr.bin/mex/mex.c b/usr.bin/mex/mex.c
new file mode 100644
index 0000000..7e6f8aa
--- /dev/null
+++ b/usr.bin/mex/mex.c
@@ -0,0 +1,105 @@
+/*
+ * Copyright (c) 2023-2025 Ian Marco Moffett and the Osmora Team.
+ * 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 Hyra 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>
+
+#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);
+    return 0;
+}