nbos

#define _GNU_SOURCE

#include "fetch.h"

#include <errno.h>

#include <stdio.h>

#include <string.h>

#include "hash.h"

#include "run.h"

/**

 * fetch() - Download a package's source tarball and verify its hash.

 * @p: Package whose @src URL and @sha256 are used.

 * @dest_path: Destination path on disk.

 *

 * Shells out to curl(1) so nb does not link libcurl. The downloaded

 * file's sha256 is compared against @p->sha256.

 *

 * Return: FETCH_OK_VAL on success, a tagged error otherwise.

 */

fetch_error fetch(const pkg *p, const char *dest_path) {

    // TODO: replace this with execvpe or libcurl

    char *const argv[] = {

        "/usr/bin/curl",

        "-fsSL",

        "--retry", "3",

        "--retry-delay", "2",

        "-o", (char *)dest_path,

        (char *)p->src,

        nullptr,

    };

    char *const envp[] = { nullptr };

    char log_path[4096];

    int n = snprintf(log_path, sizeof(log_path), "%s.fetch.log", dest_path);

    if (n < 0 || (size_t)n >= sizeof(log_path)) {

        return (fetch_error){

            .kind = FETCH_E_IO,

            .url = p->src,

            .errno_val = ENAMETOOLONG,

        };

    }

    run_error rerr = run("/usr/bin/curl", argv, envp, nullptr, log_path);

    if (rerr.kind != RUN_OK) {

        fetch_error fe = {

            .kind = FETCH_E_NETWORK,

            .url = p->src,

            .errno_val = 0,

        };

        if (rerr.kind == RUN_E_SPAWN || rerr.kind == RUN_E_IO) {

            fe.kind = FETCH_E_IO;

            fe.errno_val = rerr.errno_val;

        }

        return fe;

    }

    char actual[65] = {0};

    if (!sha256_verify_file(dest_path, p->sha256, actual)) {

        return (fetch_error){

            .kind = FETCH_E_HASH_MISMATCH,

            .url = p->src,

            .expected_sha = p->sha256,

            .actual_sha = strdup(actual),

        };

    }

    return FETCH_OK_VAL;

}