Add raw memory visualization tool to redbean

This change introduces a `-W /dev/pts/1` flag to redbean. What it does
is use the mincore() system call to create a dual-screen terminal
display that lets you troubleshoot the virtual address space. This is
useful since page faults are an important thing to consider when using a
forking web server. Now we have a colorful visualization of which pages
are going to fault and which ones are resident in memory.

The memory monitor, if enabled, spawns as a thread that just outputs
ANSI codes to the second terminal in a loop. In order to make this
happen using the new clone() polyfill, stdio is now thread safe.

This change also introduces some new demo pages to redbean. It also
polishes the demos we already have, to look a bit nicer and more
presentable for the upcoming release, with better explanations too.
This commit is contained in:
Justine Tunney 2022-05-14 04:33:58 -07:00
parent 578cb21591
commit 80b211e314
106 changed files with 1483 additions and 592 deletions

View file

@ -21,14 +21,16 @@
#define _POSIX2_VERSION _POSIX_VERSION
#define _XOPEN_VERSION 700
#define EOF -1 /* end of file */
#define WEOF -1u /* end of file (multibyte) */
#define _IOFBF 0 /* fully buffered */
#define _IOLBF 1 /* line buffered */
#define _IONBF 2 /* no buffering */
#define SEEK_SET 0 /* relative to beginning */
#define SEEK_CUR 1 /* relative to current position */
#define SEEK_END 2 /* relative to end */
#define EOF -1 /* end of file */
#define WEOF -1u /* end of file (multibyte) */
#define _IOFBF 0 /* fully buffered */
#define _IOLBF 1 /* line buffered */
#define _IONBF 2 /* no buffering */
#define SEEK_SET 0 /* relative to beginning */
#define SEEK_CUR 1 /* relative to current position */
#define SEEK_END 2 /* relative to end */
#define __WALL 0x40000000 /* Wait on all children, regardless of type */
#define __WCLONE 0x80000000 /* Wait only on non-SIGCHLD children */
#define SIG_ERR ((void (*)(int))(-1))
#define SIG_DFL ((void *)0)
@ -147,6 +149,7 @@ int linkat(int, const char *, int, const char *, int);
int lstat(const char *, struct stat *);
int lutimes(const char *, const struct timeval[2]);
int madvise(void *, uint64_t, int);
int mincore(void *, size_t, unsigned char *);
int mkdir(const char *, uint32_t);
int mkdirat(int, const char *, uint32_t);
int mkfifo(const char *, uint32_t);