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#include <assert.h>
#include <camellia/fs/dir.h>
#include <camellia/fs/misc.h>
#include <camellia/syscalls.h>
#include <errno.h>
#include <string.h>
#include <sys/param.h>
#include <unistd.h>
typedef struct Handle {
int delegate;
int plen;
char path[];
} Handle;
static int
dir_seglen(const char *path)
{
/* if path contains /, return its position + 1
* otherwise, return strlen */
int len = 0;
while (path[len]) {
if (path[len] == '/') {
len++;
break;
}
len++;
}
return len;
}
static int
find_injects(const char *injects[], const char *path, int plen, struct dirbuild *db)
{
// TODO deduplicate
const char *inj;
int matches = 0;
assert(plen >= 1);
assert(path[plen-1] == '/');
while ((inj = *injects++)) {
int ilen = strlen(inj);
if (plen < ilen && memcmp(path, inj, plen) == 0) {
if (db) {
/* inj[plen-1] == '/' */
const char *ent = inj + plen;
dir_appendl(db, ent, dir_seglen(ent));
}
matches++;
}
}
return matches;
}
void
fs_dirinject2(const char *injects[])
{
const size_t buflen = 4096;
char *buf = malloc(buflen);
if (!buf) exit(1);
for (;;) {
struct ufs_request req;
hid_t reqh = _sys_fs_wait(buf, buflen, &req);
if (reqh < 0) break;
Handle *hndl = req.id;
switch (req.op) {
case VFSOP_OPEN: {
if (buf[req.len - 1] == '/') {
if (find_injects(injects, buf, req.len, NULL) > 0) {
/* opening a directory that we're injecting into */
hndl = malloc(sizeof(Handle) + req.len);
if (hndl == NULL) {
_sys_fs_respond(reqh, NULL, -EGENERIC, 0);
break;
}
/* ignore errors from _sys_open */
hndl->delegate = _sys_open(buf, req.len, req.flags);
hndl->plen = req.len;
memcpy(hndl->path, buf, hndl->plen);
_sys_fs_respond(reqh, hndl, 0, 0);
break;
}
}
/* default behaviour */
forward_open(reqh, buf, req.len, req.flags);
break;
}
case VFSOP_CLOSE: {
if (hndl->delegate >= 0) {
close(hndl->delegate);
}
free(hndl);
_sys_fs_respond(reqh, NULL, 0, 0);
break;
}
case VFSOP_READ:
case VFSOP_GETSIZE: {
struct dirbuild db;
char *target = NULL;
if (req.op == VFSOP_READ) {
target = buf;
}
req.capacity = MIN(req.capacity, buflen);
dir_start(&db, req.offset, target, req.capacity);
find_injects(injects, hndl->path, hndl->plen, &db);
if (hndl->delegate >= 0) {
dir_append_from(&db, hndl->delegate);
}
_sys_fs_respond(reqh, target, dir_finish(&db), 0);
break;
}
default: {
_sys_fs_respond(reqh, NULL, -1, 0);
break;
}
}
}
exit(0);
}
void
fs_dirinject(const char *path) {
fs_dirinject2((const char*[]){ path, NULL });
}
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