mirrors/cosmopolitan
1
0
Fork 0
mirror of https://github.com/jart/cosmopolitan.git synced 2025-08-07 10:20:29 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

GetProgramExecutableName fixes for _ and -$SHELL

Browse source 
- `_` was getting clobbered by a lack of a return at the end of the
  CopyString block.

- `_` may need to be absolutized.

- Handle the special case of `argv[0]` equal to -$SHELL.
This commit is contained in:
Jōshin 2023-12-04 00:36:59 -05:00
parent 2a3813c6cf
commit e999d6852a
No known key found for this signature in database
1 changed files with 43 additions and 28 deletions
Download patch file Download diff file Expand all files Collapse all files

71
libc/calls/getprogramexecutablename.greg.c
View file

@ -23,6 +23,7 @@
#include "libc/cosmo.h"
#include "libc/dce.h"
#include "libc/errno.h"
#include "libc/intrin/getenv.internal.h"
#include "libc/serialize.h"
#include "libc/limits.h"
#include "libc/macros.internal.h"
@ -49,6 +50,38 @@ static inline int IsAlpha(int c) {
return ('A' <= c && c <= 'Z') || ('a' <= c && c <= 'z');
}
static inline const char *BaseName(const char *path) {
const char *b = strrchr(path, '/');
return b ? b + 1 : path;
}
static inline bool TryAbsolutize(char *q) {
char c;
char *p = g_prog.u.buf;
char *e = p + sizeof(g_prog.u.buf);
if (*q != '/') {
if (q[0] == '.' && q[1] == '/') {
q += 2;
}
int got = __getcwd(p, e - p - 1 - 4); // for / and .com
if (got != -1) {
p += got - 1;
*p++ = '/';
}
}
while ((c = *q++)) {
if (p + 1 + 4 < e) { // for nul and .com
*p++ = c;
}
}
*p = 0;
if (!sys_faccessat(AT_FDCWD, g_prog.u.buf, F_OK, 0)) return true;
p = WRITE32LE(p, READ32LE(".com"));
*p = 0;
if (!sys_faccessat(AT_FDCWD, g_prog.u.buf, F_OK, 0)) return true;
return false;
}
static inline void InitProgramExecutableNameImpl(void) {
if (IsWindows()) {
@ -71,7 +104,7 @@ static inline void InitProgramExecutableNameImpl(void) {
return;
}
char c, *q;
char c, *q, *shell;
if (IsMetal()) {
q = APE_COM_NAME;
goto CopyString;
@ -80,38 +113,19 @@ static inline void InitProgramExecutableNameImpl(void) {
// if argv[0] exists then turn it into an absolute path. we also try
// adding a .com suffix since the ape auto-appends it when resolving
if ((q = __argv[0])) {
char *p = g_prog.u.buf;
char *e = p + sizeof(g_prog.u.buf);
if (*q != '/') {
if (q[0] == '.' && q[1] == '/') {
q += 2;
}
int got = __getcwd(p, e - p - 1 - 4); // for / and .com
if (got != -1) {
p += got - 1;
*p++ = '/';
}
if (*q == '-' && (shell = __getenv(__envp, "SHELL").s) &&
!strcmp(q + 1, BaseName(shell))) {
q = shell;
}
while ((c = *q++)) {
if (p + 1 + 4 < e) { // for nul and .com
*p++ = c;
}
if (TryAbsolutize(q)) {
return;
}
*p = 0;
if (!sys_faccessat(AT_FDCWD, g_prog.u.buf, F_OK, 0)) return;
p = WRITE32LE(p, READ32LE(".com"));
*p = 0;
if (!sys_faccessat(AT_FDCWD, g_prog.u.buf, F_OK, 0)) return;
}
// if getenv("_") exists then use that
for (char **ep = __envp; (q = *ep); ++ep) {
if (*q++ == '_' && *q++ == '=') {
goto CopyString;
if ((q = __getenv(__envp, "_").s) && TryAbsolutize(q)) {
return;
}
}
// if argv[0] doesn't exist, then fallback to interpreter name
// if argv[0] and _ don't exist, then fallback to interpreter name
ssize_t got;
char *b = g_prog.u.buf;
size_t n = sizeof(g_prog.u.buf) - 1;
@ -146,6 +160,7 @@ static inline void InitProgramExecutableNameImpl(void) {
}
}
*p = 0;
return;
}
// if we don't even have that then empty the string