memory leak in pmh_markdown_to_elements

[NotmebutWind]

input value :#@$^^&^(
1 enter the project code path
2 CC=gcc -fsanitize=address make
3 ./highligher #@$^^&^(
4 program crash and the stacktrace is :
Direct leak of 248 byte(s) in 1 object(s) allocated from:
#0 0x7fea12e49867 in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
#1 0x5579e98e3dd0 in mk_parser_data /opt1/software/peg-markdown-highlight/pmh_parser.c:153
#2 0x5579e98e58d9 in pmh_markdown_to_elements /opt1/software/peg-markdown-highlight/pmh_parser.c:516
#3 0x5579e9942d2e in main /opt1/software/peg-markdown-highlight/highlighter.c:75

[NotmebutWind]

also

==937359==ERROR: LeakSanitizer: detected memory leaks

Direct leak of 1024 byte(s) in 1 object(s) allocated from:
#0 0x7fea12e49867 in __interceptor_malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:145
#1 0x5579e9942806 in get_contents /opt1/software/peg-markdown-highlight/highlighter.c:22
#2 0x5579e9942d0e in main /opt1/software/peg-markdown-highlight/highlighter.c:74
#3 0x7fea12b96d8f in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58