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#define _POSIX_C_SOURCE 200809L
#define _XOPEN_SOURCE 700
#include "Path/Path.h"
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
static const char output_prefix[] = "yapssg_";
static int checked_add(size_t left, size_t right, size_t *sum) {
if (left > SIZE_MAX - right) {
return -1;
}
*sum = left + right;
return 0;
}
static char *duplicate_string(const char *value) {
size_t length = strlen(value);
char *copy = malloc(length + 1);
if (copy != NULL) {
memcpy(copy, value, length + 1);
}
return copy;
}
char *path_join(const char *left, const char *right) {
size_t left_length = strlen(left);
size_t right_length = strlen(right);
int needs_separator = left_length > 0 && left[left_length - 1] != '/';
size_t path_length;
size_t allocation_size;
char *path;
if (checked_add(left_length, (size_t)needs_separator, &path_length) != 0 ||
checked_add(path_length, right_length, &path_length) != 0 ||
checked_add(path_length, 1, &allocation_size) != 0) {
return NULL;
}
path = malloc(allocation_size);
if (path == NULL) {
return NULL;
}
memcpy(path, left, left_length);
if (needs_separator) {
path[left_length++] = '/';
}
memcpy(path + left_length, right, right_length + 1);
return path;
}
char *path_make_default_output(const char *input_path) {
const char *end = input_path + strlen(input_path);
const char *base;
size_t parent_length;
size_t base_length;
size_t prefix_length = sizeof(output_prefix) - 1;
size_t output_length;
size_t allocation_size;
char *output_path;
while (end > input_path + 1 && end[-1] == '/') {
--end;
}
base = end;
while (base > input_path && base[-1] != '/') {
--base;
}
parent_length = (size_t)(base - input_path);
base_length = (size_t)(end - base);
if (base_length == 0) {
return NULL;
}
if (checked_add(parent_length, prefix_length, &output_length) != 0 ||
checked_add(output_length, base_length, &output_length) != 0 ||
checked_add(output_length, 1, &allocation_size) != 0) {
return NULL;
}
output_path = malloc(allocation_size);
if (output_path == NULL) {
return NULL;
}
memcpy(output_path, input_path, parent_length);
memcpy(output_path + parent_length, output_prefix, prefix_length);
memcpy(output_path + parent_length + prefix_length, base, base_length);
output_path[parent_length + prefix_length + base_length] = '\0';
return output_path;
}
char *path_resolve_new(const char *path) {
char *path_copy = duplicate_string(path);
char *slash;
char *parent;
char *resolved_parent;
char *resolved_path;
const char *base;
size_t length;
if (path_copy == NULL) {
return NULL;
}
length = strlen(path_copy);
while (length > 1 && path_copy[length - 1] == '/') {
path_copy[--length] = '\0';
}
slash = strrchr(path_copy, '/');
if (slash == NULL) {
parent = duplicate_string(".");
base = path_copy;
} else if (slash == path_copy) {
parent = duplicate_string("/");
base = slash + 1;
} else {
*slash = '\0';
parent = duplicate_string(path_copy);
base = slash + 1;
}
if (parent == NULL || base[0] == '\0') {
free(parent);
free(path_copy);
return NULL;
}
resolved_parent = realpath(parent, NULL);
free(parent);
if (resolved_parent == NULL) {
free(path_copy);
return NULL;
}
resolved_path = path_join(resolved_parent, base);
free(resolved_parent);
free(path_copy);
return resolved_path;
}
char *path_resolve_from_file(const char *file_path, const char *relative_path) {
const char *slash;
size_t directory_length;
size_t relative_length;
size_t path_length;
size_t allocation_size;
char *path;
if (relative_path[0] == '/') {
return duplicate_string(relative_path);
}
slash = strrchr(file_path, '/');
directory_length = slash == NULL ? 0 : (size_t)(slash - file_path + 1);
relative_length = strlen(relative_path);
if (checked_add(directory_length, relative_length, &path_length) != 0 ||
checked_add(path_length, 1, &allocation_size) != 0) {
return NULL;
}
path = malloc(allocation_size);
if (path == NULL) {
return NULL;
}
memcpy(path, file_path, directory_length);
memcpy(path + directory_length, relative_path, relative_length + 1);
return path;
}
int path_is_within(const char *parent, const char *candidate) {
size_t parent_length = strlen(parent);
if (parent_length == 1 && parent[0] == '/') {
return candidate[0] == '/';
}
return strncmp(parent, candidate, parent_length) == 0 &&
(candidate[parent_length] == '\0' || candidate[parent_length] == '/');
}
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