busybox/networking/httpd_post_upload.txt

POST upload example:

post_upload.htm
===============
<html>
<body>
<form action=/cgi-bin/post_upload.cgi method=post enctype=multipart/form-data>
File to upload: <input type=file name=file1> <input type=submit>
</form>


post_upload.cgi
===============
#!/bin/sh

# POST upload format:
# -----------------------------29995809218093749221856446032^M
# Content-Disposition: form-data; name="file1"; filename="..."^M
# Content-Type: application/octet-stream^M
# ^M    <--------- headers end with empty line
# file contents
# file contents
# file contents
# ^M    <--------- extra empty line
# -----------------------------29995809218093749221856446032--^M

# Beware: bashism $'\r' is used to handle ^M

file=/tmp/$$-$RANDOM

# CGI output must start with at least empty line (or headers)
printf '\r\n'

IFS=$'\r'
read -r delim_line

IFS=''
delim_line="${delim_line}--"$'\r'

while read -r line; do
    test "$line" = '' && break
    test "$line" = $'\r' && break
done

# This will not work well for binary files: bash 3.2 is upset
# by reading NUL bytes and loses chunks of data.
# If you are not bothered by having junk appended to the uploaded file,
# consider using simple "cat >file" instead of the entire
# fragment below.

while read -r line; do

    while test "$line" = $'\r'; do
	read -r line
	test "$line" = "$delim_line" && {
	    # Aha! Empty line + delimiter! All done
	    cat <<EOF
<html>
<body>
File upload has been accepted
EOF
	    exit 0
	}
	# Empty line + NOT delimiter. Save empty line,
	# and go check next line
	printf "%s\n" $'\r' -vC >&3
    done
    # Not empty line - just save
    printf "%s\n" "$line" -vC >&3
done 3>"$file"

cat <<EOF
<html>
<body>
File upload was not terminated with '$delim_line' - ??!
EOF
1	POST upload example:
2
3	post_upload.htm
4	===============
5	<html>
6	<body>
7	<form action=/cgi-bin/post_upload.cgi method=post enctype=multipart/form-data>
8	File to upload: <input type=file name=file1> <input type=submit>
9	</form>
10
11
12	post_upload.cgi
13	===============
14	#!/bin/sh
15
16	# POST upload format:
17	# -----------------------------29995809218093749221856446032^M
18	# Content-Disposition: form-data; name="file1"; filename="..."^M
19	# Content-Type: application/octet-stream^M
20	# ^M <--------- headers end with empty line
21	# file contents
22	# file contents
23	# file contents
24	# ^M <--------- extra empty line
25	# -----------------------------29995809218093749221856446032--^M
26
27	# Beware: bashism $'\r' is used to handle ^M
28
29	file=/tmp/$$-$RANDOM
30
31	# CGI output must start with at least empty line (or headers)
32	printf '\r\n'
33
34	IFS=$'\r'
35	read -r delim_line
36
37	IFS=''
38	delim_line="${delim_line}--"$'\r'
39
40	while read -r line; do
41	test "$line" = '' && break
42	test "$line" = $'\r' && break
43	done
44
45	# This will not work well for binary files: bash 3.2 is upset
46	# by reading NUL bytes and loses chunks of data.
47	# If you are not bothered by having junk appended to the uploaded file,
48	# consider using simple "cat >file" instead of the entire
49	# fragment below.
50
51	while read -r line; do
52
53	while test "$line" = $'\r'; do
54	read -r line
55	test "$line" = "$delim_line" && {
56	# Aha! Empty line + delimiter! All done
57	cat <<EOF
58	<html>
59	<body>
60	File upload has been accepted
61	EOF
62	exit 0
63	}
64	# Empty line + NOT delimiter. Save empty line,
65	# and go check next line
66	printf "%s\n" $'\r' -vC >&3
67	done
68	# Not empty line - just save
69	printf "%s\n" "$line" -vC >&3
70	done 3>"$file"
71
72	cat <<EOF
73	<html>
74	<body>
75	File upload was not terminated with '$delim_line' - ??!
76	EOF