graphene/LibOS/shim/test/regression/fs_long_path.c

#include <string.h>
#include <stdio.h>
#include <stdlib.h>

#define FILENAME_MAX_LENGTH 255
#define PATH "tmp/"
#define MSG "Hello World"

int main(int argc, char** argv) {
    size_t rets;
    int reti;
    char filename[FILENAME_MAX_LENGTH];
    memset(filename, 'a', sizeof(filename));
    filename[FILENAME_MAX_LENGTH-1] = '\0';

    char filepath[sizeof(PATH) + sizeof(filename) - 1];
    strcpy(filepath, PATH);
    strcat(filepath, filename);

    printf("filepath = %s (len = %lu)\n", filepath, strlen(filepath));

    /* write to file */
    FILE* fp = fopen(filepath, "w");
    if (fp == NULL) {
        perror("fopen failed");
        return 1;
    }

    rets = fwrite(MSG, sizeof(MSG), 1, fp); /* with NULL byte for later printf */
    if (rets != 1) {
        perror("fwrite failed");
        return 1;
    }

    reti = fclose(fp);
    if (reti) {
        perror("fclose failed");
        return 1;
    }

    /* read from same file */
    fp = fopen(filepath, "r");
    if (fp == NULL) {
        perror("fopen failed");
        return 1;
    }

    char buf[256];
    clearerr(fp);
    rets = fread(buf, sizeof(buf), 1, fp);
    if (rets != 1 && ferror(fp)) {
        perror("fread failed");
        return 1;
    }

    reti = fclose(fp);
    if (reti) {
        perror("fclose failed");
        return 1;
    }

    reti = printf("Successfully read from file: %s\n", buf);
    if (reti < 0) {
        perror("printf failed");
        return 1;
    }

    return 0;
}