blob: d3c5d071d62059843a715e2778c59c4e8ab16009 [file] [log] [blame]
/*
.Some useful path tools.
.ASCII only for now.
.Written by Ray Donnelly in 2014.
.Licensed under CC0 (and anything.
.else you need to license it under).
.No warranties whatsoever.
.email: <mingw.android@gmail.com>.
*/
#include <stdlib.h>
#include <limits.h>
#include <stdio.h>
#include <string.h>
#if defined(__linux__) || defined(__CYGWIN__) || defined(__MSYS__)
#include <alloca.h>
#endif
#include <unistd.h>
/* If you don't define this, then get_executable_path()
can only use argv[0] which will often not work well */
#define IMPLEMENT_SYS_GET_EXECUTABLE_PATH
#if defined(IMPLEMENT_SYS_GET_EXECUTABLE_PATH)
#if defined(__linux__) || defined(__CYGWIN__) || defined(__MSYS__)
/* Nothing needed, unistd.h is enough. */
#elif defined(__APPLE__)
#include <mach-o/dyld.h>
#elif defined(_WIN32)
// widl can't include the normal Windows headers due to providing its own winnt.h (and others).
#ifdef __x86_64__
__attribute__((dllimport)) long GetModuleFileNameA (long hModule, void* lpFilename, long nSize);
#else
__attribute__((dllimport)) long __attribute__((__stdcall__)) GetModuleFileNameA (long hModule, void* lpFilename, long nSize);
#endif
#endif
#else
#define PATH_MAX 260
#endif /* defined(IMPLEMENT_SYS_GET_EXECUTABLE_PATH) */
#include "pathtools.h"
char *
malloc_copy_string(char const * original)
{
char * result = (char *) malloc (sizeof (char*) * strlen (original)+1);
if (result != NULL)
{
strcpy (result, original);
}
return result;
}
void
sanitise_path(char * path)
{
size_t path_size = strlen (path);
/* Replace any '\' with '/' */
char * path_p = path;
while ((path_p = strchr (path_p, '\\')) != NULL)
{
*path_p = '/';
}
/* Replace any '//' with '/' */
path_p = path;
while ((path_p = strstr (path_p, "//")) != NULL)
{
memmove (path_p, path_p + 1, path_size--);
}
return;
}
char *
get_relative_path(char const * from_in, char const * to_in)
{
size_t from_size = (from_in == NULL) ? 0 : strlen (from_in);
size_t to_size = (to_in == NULL) ? 0 : strlen (to_in);
size_t max_size = (from_size + to_size) * 2 + 4;
char * scratch_space = (char *) alloca (from_size + 1 + to_size + 1 + max_size + max_size);
char * from;
char * to;
char * common_part;
char * result;
size_t count;
/* No to, return "./" */
if (to_in == NULL)
{
return malloc_copy_string ("./");
}
/* If alloca failed or no from was given return a copy of to */
if ( from_in == NULL
|| scratch_space == NULL )
{
return malloc_copy_string (to_in);
}
from = scratch_space;
strcpy (from, from_in);
to = from + from_size + 1;
strcpy (to, to_in);
common_part = to + to_size + 1;
result = common_part + max_size;
simplify_path (from);
simplify_path (to);
result[0] = '\0';
size_t match_size_dirsep = 0; /* The match size up to the last /. Always wind back to this - 1 */
size_t match_size = 0; /* The running (and final) match size. */
size_t largest_size = (from_size > to_size) ? from_size : to_size;
int to_final_is_slash = (to[to_size-1] == '/') ? 1 : 0;
char from_c;
char to_c;
for (match_size = 0; match_size < largest_size; ++match_size)
{
/* To simplify the logic, always pretend the strings end with '/' */
from_c = (match_size < from_size) ? from[match_size] : '/';
to_c = (match_size < to_size) ? to[match_size] : '/';
if (from_c != to_c)
{
if (from_c != '\0' || to_c != '\0')
{
match_size = match_size_dirsep;
}
break;
}
else if (from_c == '/')
{
match_size_dirsep = match_size;
}
}
strncpy (common_part, from, match_size);
common_part[match_size] = '\0';
from += match_size;
to += match_size;
size_t ndotdots = 0;
char const* from_last = from + strlen(from) - 1;
while ((from = strchr (from, '/')) && from != from_last)
{
++ndotdots;
++from;
}
for (count = 0; count < ndotdots; ++count)
{
strcat(result, "../");
}
if (strlen(to) > 0)
{
strcat(result, to+1);
}
/* Make sure that if to ends with '/' result does the same, and
vice-versa. */
size_t size_result = strlen(result);
if ((to_final_is_slash == 1)
&& (!size_result || result[size_result-1] != '/'))
{
strcat (result, "/");
}
else if (!to_final_is_slash
&& size_result && result[size_result-1] == '/')
{
result[size_result-1] = '\0';
}
return malloc_copy_string (result);
}
void
simplify_path(char * path)
{
ssize_t n_toks = 1; /* in-case we need an empty initial token. */
ssize_t i, j;
size_t tok_size;
size_t in_size = strlen (path);
int it_ended_with_a_slash = (path[in_size - 1] == '/') ? 1 : 0;
char * result = path;
sanitise_path(result);
char * result_p = result;
do
{
++n_toks;
++result_p;
} while ((result_p = strchr (result_p, '/')) != NULL);
result_p = result;
char const ** toks = (char const **) alloca (sizeof (char const*) * n_toks);
n_toks = 0;
do
{
if (result_p > result)
{
*result_p++ = '\0';
}
else if (*result_p == '/')
{
/* A leading / creates an empty initial token. */
toks[n_toks++] = result_p;
*result_p++ = '\0';
}
toks[n_toks++] = result_p;
} while ((result_p = strchr (result_p, '/')) != NULL);
/* Remove all non-leading '.' and any '..' we can match
with an earlier forward path (i.e. neither '.' nor '..') */
for (i = 1; i < n_toks; ++i)
{
int removals[2] = { -1, -1 };
if ( strcmp (toks[i], "." ) == 0)
{
removals[0] = i;
}
else if ( strcmp (toks[i], ".." ) == 0)
{
/* Search backwards for a forward path to collapse.
If none are found then the .. also stays. */
for (j = i - 1; j > -1; --j)
{
if ( strcmp (toks[j], "." )
&& strcmp (toks[j], ".." ) )
{
removals[0] = j;
removals[1] = i;
break;
}
}
}
for (j = 0; j < 2; ++j)
{
if (removals[j] >= 0) /* Can become -2 */
{
--n_toks;
memmove (&toks[removals[j]], &toks[removals[j]+1], (n_toks - removals[j])*sizeof (char*));
--i;
if (!j)
{
--removals[1];
}
}
}
}
result_p = result;
for (i = 0; i < n_toks; ++i)
{
tok_size = strlen(toks[i]);
memmove (result_p, toks[i], tok_size);
result_p += tok_size;
if ((!i || tok_size) && ((i < n_toks - 1) || it_ended_with_a_slash == 1))
{
*result_p = '/';
++result_p;
}
}
*result_p = '\0';
}
/* Returns actual_to by calculating the relative path from -> to and
applying that to actual_from. An assumption that actual_from is a
dir is made, and it may or may not end with a '/' */
char const *
get_relocated_path (char const * from, char const * to, char const * actual_from)
{
char const * relative_from_to = get_relative_path (from, to);
char * actual_to = (char *) malloc (strlen(actual_from) + 2 + strlen(relative_from_to));
return actual_to;
}
int
get_executable_path(char const * argv0, char * result, ssize_t max_size)
{
char * system_result = (char *) alloca (max_size);
ssize_t system_result_size = -1;
ssize_t result_size = -1;
if (system_result != NULL)
{
#if defined(IMPLEMENT_SYS_GET_EXECUTABLE_PATH)
#if defined(__linux__) || defined(__CYGWIN__) || defined(__MSYS__)
system_result_size = readlink("/proc/self/exe", system_result, max_size);
#elif defined(__APPLE__)
uint32_t bufsize = (uint32_t)max_size;
if (_NSGetExecutablePath(system_result, &bufsize) == 0)
{
system_result_size = strlen (system_result);
}
#elif defined(_WIN32)
unsigned long bufsize = (unsigned long)max_size;
system_result_size = GetModuleFileNameA(0, system_result, bufsize);
if (system_result_size == 0 || system_result_size == (ssize_t)bufsize)
{
/* Error, possibly not enough space. */
system_result_size = -1;
}
else
{
/* Early conversion to unix slashes instead of more changes
everywhere else .. */
char * winslash;
system_result[system_result_size] = '\0';
while ((winslash = strchr (system_result, '\\')) != NULL)
{
*winslash = '/';
}
}
#else
#warning "Don't know how to get executable path on this system"
#endif
#endif /* defined(IMPLEMENT_SYS_GET_EXECUTABLE_PATH) */
}
/* Use argv0 as a default in-case of failure */
if (system_result_size != -1)
{
strncpy (result, system_result, system_result_size);
result[system_result_size] = '\0';
}
else
{
if (argv0 != NULL)
{
strncpy (result, argv0, max_size);
char *slash;
while ((slash = strchr(result, '\\')) != NULL) {
*slash++ = '/';
}
result[max_size-1] = '\0';
}
else
{
result[0] = '\0';
}
}
result_size = strlen (result);
return result_size;
}
char const *
strip_n_prefix_folders(char const * path, size_t n)
{
if (path == NULL)
{
return NULL;
}
if (path[0] != '/')
{
return path;
}
char const * last = path;
while (n-- && path != NULL)
{
last = path;
path = strchr (path + 1, '/');
}
return (path == NULL) ? last : path;
}
void
strip_n_suffix_folders(char * path, size_t n)
{
if (path == NULL)
{
return;
}
while (n--)
{
if (strrchr (path + 1, '/'))
{
*strrchr (path + 1, '/') = '\0';
}
else
{
return;
}
}
return;
}
size_t
split_path_list(char const * path_list, char split_char, char *** arr)
{
size_t path_count;
size_t path_list_size;
char const * path_list_p;
path_list_p = path_list;
if (path_list == NULL || path_list[0] == '\0')
{
return 0;
}
path_list_size = strlen (path_list);
path_count = 0;
do
{
++path_count;
++path_list_p;
}
while ((path_list_p = strchr (path_list_p, split_char)) != NULL);
/* allocate everything in one go. */
char * all_memory = (char *) malloc (sizeof (char *) * path_count + strlen(path_list) + 1);
if (all_memory == NULL)
return 0;
*arr = (char **)all_memory;
all_memory += sizeof (char *) * path_count;
path_count = 0;
path_list_p = path_list;
char const * next_path_list_p = 0;
do
{
next_path_list_p = strchr (path_list_p, split_char);
if (next_path_list_p != NULL)
{
++next_path_list_p;
}
size_t this_size = (next_path_list_p != NULL)
? next_path_list_p - path_list_p - 1
: &path_list[path_list_size] - path_list_p;
memcpy (all_memory, path_list_p, this_size);
all_memory[this_size] = '\0';
(*arr)[path_count++] = all_memory;
all_memory += this_size + 1;
} while ((path_list_p = next_path_list_p) != NULL);
return path_count;
}
char *
get_relocated_path_list(char const * from, char const * to_path_list)
{
char exe_path[PATH_MAX];
char * temp;
get_executable_path (NULL, &exe_path[0], sizeof (exe_path) / sizeof (exe_path[0]));
if ((temp = strrchr (exe_path, '/')) != NULL)
{
temp[1] = '\0';
}
char **arr = NULL;
/* Ask Alexey why he added this. Are we not 100% sure
that we're dealing with unix paths here? */
char split_char = ':';
if (strchr (to_path_list, ';'))
{
split_char = ';';
}
size_t count = split_path_list (to_path_list, split_char, &arr);
int result_size = 1 + (count - 1); /* count - 1 is for ; delim. */
size_t exe_path_size = strlen (exe_path);
size_t i;
/* Space required is:
count * (exe_path_size + strlen (rel_to_datadir))
rel_to_datadir upper bound is:
(count * strlen (from)) + (3 * num_slashes (from))
+ strlen(arr[i]) + 1.
.. pathalogically num_slashes (from) is strlen (from)
(from = ////////) */
size_t space_required = (count * (exe_path_size + 4 * strlen (from))) + count - 1;
for (i = 0; i < count; ++i)
{
space_required += strlen (arr[i]);
}
char * scratch = (char *) alloca (space_required);
if (scratch == NULL)
return NULL;
for (i = 0; i < count; ++i)
{
char * rel_to_datadir = get_relative_path (from, arr[i]);
scratch[0] = '\0';
arr[i] = scratch;
strcat (scratch, exe_path);
strcat (scratch, rel_to_datadir);
simplify_path (arr[i]);
size_t arr_i_size = strlen (arr[i]);
result_size += arr_i_size;
scratch = arr[i] + arr_i_size + 1;
}
char * result = (char *) malloc (result_size);
if (result == NULL)
{
return NULL;
}
result[0] = '\0';
for (i = 0; i < count; ++i)
{
strcat (result, arr[i]);
if (i != count-1)
{
#if defined(_WIN32)
strcat (result, ";");
#else
strcat (result, ":");
#endif
}
}
free ((void*)arr);
return result;
}
char *
single_path_relocation(const char *from, const char *to)
{
#if defined(__MINGW32__)
char exe_path[PATH_MAX];
get_executable_path (NULL, &exe_path[0], sizeof(exe_path)/sizeof(exe_path[0]));
if (strrchr (exe_path, '/') != NULL)
{
strrchr (exe_path, '/')[1] = '\0';
}
char * rel_to_datadir = get_relative_path (from, to);
strcat (exe_path, rel_to_datadir);
simplify_path (&exe_path[0]);
return malloc_copy_string(exe_path);
#else
return malloc_copy_string(to);
#endif
}
char *
pathlist_relocation(const char *from_path, const char *to_path_list)
{
#if defined(__MINGW32__)
static char stored_path[PATH_MAX];
static int stored = 0;
if (stored == 0)
{
char const * relocated = get_relocated_path_list(from_path, to_path_list);
strncpy (stored_path, relocated, PATH_MAX);
stored_path[PATH_MAX-1] = '\0';
free ((void *)relocated);
stored = 1;
}
return stored_path;
#else
return (to_path_list);
#endif
}