Commit cae2a7ca authored by Richard Levitte's avatar Richard Levitte
Browse files

Smarter build of system error text database 



We stored copies of the system error texts in a fixed line size array,
which is a huge waste.  Instead, use a static memory pool and pack all
the string in there.  The wasted space at the end, if any, gives us
some leeway for longer strings than we have measured so far.

Reviewed-by: default avatarMatt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/7681)

(cherry picked from commit 2c5b6bbb)
parent 5970d480

crypto/err/err.c

+14 −5
Original line number Diff line number Diff line
@@ -181,8 +181,9 @@ static ERR_STRING_DATA *int_err_get_item(const ERR_STRING_DATA *d) 
}



#ifndef OPENSSL_NO_ERR

/* A measurement on Linux 2018-11-21 showed about 3.5kib */

# define SPACE_SYS_STR_REASONS 4 * 1024

# define NUM_SYS_STR_REASONS 127

# define LEN_SYS_STR_REASON 32



static ERR_STRING_DATA SYS_str_reasons[NUM_SYS_STR_REASONS + 1];

/*
@@ -198,7 +199,9 @@ static ERR_STRING_DATA SYS_str_reasons[NUM_SYS_STR_REASONS + 1]; 
static void build_SYS_str_reasons(void)

{

    /* OPENSSL_malloc cannot be used here, use static storage instead */

    static char strerror_tab[NUM_SYS_STR_REASONS][LEN_SYS_STR_REASON];

    static char strerror_pool[SPACE_SYS_STR_REASONS];

    char *cur = strerror_pool;

    size_t cnt = 0;

    static int init = 1;

    int i;
@@ -213,9 +216,15 @@ static void build_SYS_str_reasons(void) 


        str->error = ERR_PACK(ERR_LIB_SYS, 0, i);

        if (str->string == NULL) {

            char (*dest)[LEN_SYS_STR_REASON] = &(strerror_tab[i - 1]);

            if (openssl_strerror_r(i, *dest, sizeof(*dest)))

                str->string = *dest;

            if (openssl_strerror_r(i, cur, sizeof(strerror_pool) - cnt)) {

                size_t l = strlen(cur) + 1;



                str->string = cur;

                cnt += l;

                if (cnt > sizeof(strerror_pool))

                    cnt = sizeof(strerror_pool);

                cur += l;

            }

        }

        if (str->string == NULL)

            str->string = "unknown";