ToC path:

mco_lews_url_param_decode
RT

Prototype

    MCO_RET mco_lews_url_param_decode(
        char *in_str,
        mco_size_t in_size,
        char *out_str,
        mco_size_t out_size
    );

Arguments

in_str

Pointer to the null-terminated or length-delimited input string containing URL-encoded data (e.g., "bar%20foo").

in_size

Size (in bytes) of the input buffer. If the string is null-terminated, this should include the terminator only if it is part of the data to be processed.

out_str

Pointer to the output buffer where the decoded string will be stored.

out_size

Size (in bytes) of the output buffer, including space for the null terminator.

Description

This function decodes a URL-encoded (percent-encoded) string according to RFC 3986.

It scans the input for sequences of the form %XX, where XX is a two-digit hexadecimal number, and replaces each such sequence with the corresponding byte (e.g., %20 → space character 0x20).

Invalid percent-encodings (e.g., %2z, %1) are treated as literal characters and copied as-is.

The output string is null-terminated.
    MCO_RET rc;
    char tmp_buf[1024];
    lews_connection_context_t ctx;
    ...
    /*
    // Incoming buffer contains:
    "GET /some?param1=AbC&param2=bar%20foo&param3=123&param4=bar%2zzz&param5=qqq HTTP/1.1\r\n"
    "Host: example.com\r\n"
    "Content-Type: application/x-www-form-urlencoded; charset=utf-8\r\n\r\n"
    */
    rc = mco_lews_get_query_param_str((char*)(&ctx.incoming_buf) + ctx.params_pos,
                                    ctx.params_len, "param2", tmp_buf, sizeof(tmp_buf));
    ASSERT_EQ(MCO_S_OK, rc);
    ASSERT_STREQ("bar%20foo", tmp_buf);

    rc = mco_lews_url_param_decode(tmp_buf, strlen(tmp_buf), tmp_buf, sizeof(tmp_buf));
    ASSERT_EQ(MCO_S_OK, rc);
    ASSERT_STREQ("bar foo", tmp_buf);

Return Codes

MCO_S_OK

Input successfully decoded and stored in out_str.

MCO_E_LEWS_NO_ENOUGH_MEMORY

The output buffer is too small to hold the decoded string (including the null terminator).

MCO_E_LEWS_BAD_PARAMETERS

One or more input pointers (in_str or out_str) are NULL.

Files

Header file:

mcoewslite.h

Source file:

mcoewslite.c

Library:

mcoewslite.a