myxce/src/autoscaler/scaler/scaler_misc.c

#include <math.h>
#include <stdarg.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>

#include "scaler_misc.h"
#include "utils.h"

int my_snprintf(char* buf, size_t size, const char* fmt, ...)
{
    va_list args;
    int     ret;

    va_start(args, fmt);
    ret = vsnprintf(buf, size, fmt, args);
    va_end(args);

    if (ret < 0) {
        WARN("my_snprintf: encoding error for format: %s", fmt);
        return ret;
    }
    if ((size_t)ret >= size) {
        WARN("my_snprintf: output truncated for format: %s (needed %d bytes, "
             "buffer size %zu)",
             fmt, ret + 1, size);
    }
    return ret;
}

/*
 * Create a temporary file with a unique name using mkstemp.
 * The file name is passed in as a parameter and should be a template
 * like "/tmp/as_in_XXXXXX.json". The 'X's will be replaced with a unique
 * sequence to ensure the file name is unique.
 *
 * Returns 0 on success, -1 on failure. file_name will contain the name of the
 * created file.
 */
int create_temp_file(char* file_name)
{
    // Call mkstemp to create a temporary file
    int fd = mkstemp(file_name);
    if (fd == -1) {
        ERROR("Failed to create temporary file, errno %d : %s.", errno,
              strerror(errno));
        return -1;
    }
    close(fd);
    return 0;
}

char* my_putstr(char* s)
{
    size_t len;
    char*  p;
    if (!s) {
        return s = "";
    }

    len = strlen(s);
    p   = (char*)calloc(len + 1, sizeof(char));
    if (!p) {
        SET_ERROR(ENOMEM);
        ERROR("Memory allocation failed");
        return NULL;
    }
    strcpy(p, s);
    return p;
}

/*
 * Safe string, return TRUE if both NULL or both equal, FALSE otherwise
 */
int my_strcmp(const char* p1, const char* p2)
{
    if (!p1 && !p2)
        return true;
    if (!p1 || !p2)
        return false;
    return strcmp(p1, p2) == 0;
}

void print_demand_list(scaler_demand_array_t* d_list)
{
    if (!d_list || d_list->num <= 0) {
        return;
    }
    INFO("Got DB demand List:");
    INFO("Number of demands: %d", d_list->num);
    for (int i = 0; i < d_list->num; i++) {
        scaler_demand_t* demand = &d_list->data[i];
        INFO("Demand %d: provider=%s, template=%s, count=%d", i,
             demand->tpl_id.provider_name, demand->tpl_id.template_id,
             demand->count);
    }
}

int cmp_template_id(scaler_template_id_t* p1, scaler_template_id_t* p2)
{
    if (!p1 && !p2)
        return true;
    if (!p1 || !p2)
        return false;
    return my_strcmp(p1->provider_name, p2->provider_name)
        && my_strcmp(p1->template_id, p2->template_id);
}

void print_request(void* data)
{
    scaler_request_t* request = (scaler_request_t*)data;
    if (!request) {
        return;
    }

    INFO("Request: req_id=%s, type=%d, status=%d, provider=%s, template=%s, "
         "count=%d",
         request->request_id ? request->request_id : "NULL", request->type,
         request->status,
         request->tpl_id.provider_name ? request->tpl_id.provider_name : "NULL",
         request->tpl_id.template_id ? request->tpl_id.template_id : "NULL",
         request->count);
}

static int _print_request_4_xlist(void* data, void* arg)
{
    print_request(data);
    return 0;
}

void print_request_list(xlist_t* r_list)
{
    if (!r_list) {
        return;
    }

    INFO("Got DB request List:");
    INFO("Number of requests: %d", r_list->count);

    xlist_iter(r_list, (xlist_iter_fn_t)_print_request_4_xlist, NULL);
}

void print_instance(void* p)
{
    scaler_instance_t* inst = (scaler_instance_t*)p;
    if (!inst) {
        return;
    }

    INFO("Instance: id=%s, hostname=%s, private_ip=%s, public_ip=%s, "
         "launch_time=%ld, alloc_status=%d, inst_state=%s, "
         "provider=%s, template=%s, request_id=%s, relinquish_id=%s, "
         "last_update_time=%ld",
         inst->instance_id ? inst->instance_id : "NULL",
         inst->hostname ? inst->hostname : "NULL",
         inst->private_ip ? inst->private_ip : "NULL",
         inst->public_ip ? inst->public_ip : "NULL", (long)inst->launch_time,
         inst->alloc_status, inst->inst_state ? inst->inst_state : "NULL",
         inst->tpl_id.provider_name ? inst->tpl_id.provider_name : "NULL",
         inst->tpl_id.template_id ? inst->tpl_id.template_id : "NULL",
         inst->request_id ? inst->request_id : "NULL",
         inst->relinquish_id ? inst->relinquish_id : "NULL",
         (long)inst->last_update_time);
}

static int _print_instance_4_xlist(void* data, void* arg)
{
    print_instance(data);
    return 0;
}

void print_instance_list(xlist_t* i_list)
{
    if (!i_list || i_list->count <= 0) {
        return;
    }
    INFO("Got DB instance List:");
    INFO("Number of instances: %d", i_list->count);
    xlist_iter(i_list, (xlist_iter_fn_t)_print_instance_4_xlist, NULL);
}

// Compare two floating point numbers for equality
// If the two numbers difference is within a small epsilon, consider them equal
#define DEFAULT_EPSILON 0.001
int float_cmp_ex(float a, float b, float ep)
{

    if (fabs(a - b) < ep) {
        return 0;
    }

    return 1;
}

int float_cmp(float a, float b) { return float_cmp_ex(a, b, DEFAULT_EPSILON); }