From d238518c35964e10edad52d0f1a166757e956ae6 Mon Sep 17 00:00:00 2001 From: Jonas 'Sortie' Termansen Date: Sat, 27 Dec 2014 23:43:39 +0100 Subject: [PATCH] Rewrite pager(1). --- utils/pager.cpp | 444 +++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 366 insertions(+), 78 deletions(-) diff --git a/utils/pager.cpp b/utils/pager.cpp index 7fe1eee5..6313170f 100644 --- a/utils/pager.cpp +++ b/utils/pager.cpp @@ -1,6 +1,6 @@ /******************************************************************************* - Copyright(C) Jonas 'Sortie' Termansen 2012. + Copyright(C) Jonas 'Sortie' Termansen 2014. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free @@ -22,97 +22,385 @@ #include #include + +#include +#include +#include +#include +#include +#include #include #include #include -#include -#include -#include -#include #include +#include +#include -char* stdinargv[2]; +#if !defined(VERSIONSTR) +#define VERSIONSTR "unknown version" +#endif + +struct display_entry +{ + wchar_t c; +}; + +struct pager +{ + int tty_fd; + unsigned int tty_fd_old_termmode; + int out_fd; + bool out_fd_tty; + struct winsize out_fd_winsize; + struct display_entry* display; + struct wincurpos begun_wcp; + struct wincurpos current_wcp; + mbstate_t in_ps; + mbstate_t out_ps; + const char* input_prompt_name; + size_t allowed_lines; + bool quiting; +}; + +void pager_init(struct pager* pager) +{ + if ( !isatty(pager->tty_fd = 0) ) + { + if ( (pager->tty_fd = open("/dev/tty", O_RDONLY)) < 0 ) + error(1, errno, "/dev/tty"); + if ( !isatty(pager->tty_fd) ) + error(1, errno, "/dev/tty"); + } + gettermmode(pager->tty_fd, &pager->tty_fd_old_termmode); + settermmode(pager->tty_fd, TERMMODE_KBKEY | TERMMODE_UNICODE | TERMMODE_SIGNAL); + + if ( (pager->out_fd_tty = isatty(pager->out_fd = 1)) ) + { + tcgetwinsize(pager->out_fd, &pager->out_fd_winsize); + size_t display_length = (size_t) pager->out_fd_winsize.ws_col * + (size_t) pager->out_fd_winsize.ws_row; + pager->display = (struct display_entry*) + calloc(display_length, sizeof(struct display_entry)); + if ( !pager->display ) + error(1, errno, "malloc"); + tcgetwincurpos(pager->out_fd, &pager->begun_wcp); + memcpy(&pager->current_wcp, &pager->begun_wcp, sizeof(struct wincurpos)); + pager->allowed_lines = pager->out_fd_winsize.ws_row - 1; + } + + memset(&pager->in_ps, 0, sizeof(pager->in_ps)); + memset(&pager->out_ps, 0, sizeof(pager->out_ps)); +} + +void pager_end(struct pager* pager) +{ + settermmode(pager->tty_fd, pager->tty_fd_old_termmode); + if ( pager->tty_fd != 0 ) + close(pager->tty_fd); +} + +void pager_prompt(struct pager* pager) +{ + if ( pager->input_prompt_name[0] ) + dprintf(pager->out_fd, "\e[47;30m%s\e[m\e[J", pager->input_prompt_name); + else + dprintf(pager->out_fd, ":"); + uint32_t codepoint; + while ( read(pager->tty_fd, &codepoint, sizeof(codepoint)) == sizeof(codepoint) ) + { + if ( codepoint == L'\n' || KBKEY_DECODE(codepoint) == KBKEY_DOWN ) + { + dprintf(pager->out_fd, "\r\e[J"); + pager->allowed_lines++; + return; + } + + if ( KBKEY_DECODE(codepoint) == KBKEY_PGDOWN ) + { + dprintf(pager->out_fd, "\r\e[J"); + pager->allowed_lines = pager->out_fd_winsize.ws_row - 1; + return; + } + + if ( KBKEY_DECODE(codepoint) == KBKEY_END ) + { + dprintf(pager->out_fd, "\r\e[J"); + pager->allowed_lines = SIZE_MAX; + return; + } + + if ( codepoint == L'q' || codepoint == L'Q' ) + { + dprintf(pager->out_fd, "\r\e[J"); + pager->quiting = true; + return; + } + } + error(1, errno, "/dev/tty"); +} + +bool pager_would_push_newline_scroll(struct pager* pager) +{ + return pager->out_fd_winsize.ws_row <= pager->current_wcp.wcp_row + 1; +} + +bool pager_would_push_char_overflow(struct pager* pager, wchar_t wc) +{ + if ( wc == L'\r' ) + return false; + return pager->out_fd_winsize.ws_col <= pager->current_wcp.wcp_col; +} + +bool pager_would_push_char_scroll(struct pager* pager, wchar_t wc) +{ + if ( wc == L'\n' ) + return pager_would_push_newline_scroll(pager); + if ( pager_would_push_char_overflow(pager, wc) ) + return pager_would_push_newline_scroll(pager); + return false; +} + +void pager_push_newline(struct pager* pager) +{ + if ( 0 < pager->allowed_lines && pager->allowed_lines != SIZE_MAX ) + pager->allowed_lines--; + if ( pager->current_wcp.wcp_row + 1 < pager->out_fd_winsize.ws_row ) + { + pager->current_wcp.wcp_row++; + } + else + { + if ( 0 < pager->begun_wcp.wcp_row ) + pager->begun_wcp.wcp_row--; + } + pager->current_wcp.wcp_col = 0; +} + +bool pager_is_out_of_allowed_lines(struct pager* pager, wchar_t wc) +{ + if ( pager->allowed_lines == 1 && wc != L'\n' && + pager_would_push_char_overflow(pager, wc) ) + return true; + return pager->allowed_lines == 0; +} + +void pager_push_final_char(struct pager* pager, wchar_t wc) +{ + if ( !wc ) + return; + + while ( pager_is_out_of_allowed_lines(pager, wc) ) + { + pager_prompt(pager); + if ( pager->quiting ) + return; + } + + mbstate_t ps; + memcpy(&ps, &pager->out_ps, sizeof(mbstate_t)); + char mb[MB_CUR_MAX]; + size_t mb_size = wcrtomb(mb, wc, &ps); + if ( mb_size == (size_t) -1 ) + { + memset(&pager->out_ps, 0, sizeof(pager->out_ps)); + return; + } + + if ( writeall(pager->out_fd, mb, mb_size) < mb_size ) + error(1, errno, "write: "); + memcpy(&pager->out_ps, &ps, sizeof(mbstate_t)); + + if ( wc == L'\n' ) + { + pager_push_newline(pager); + } + else if ( wc == L'\t' ) + { + if ( pager_would_push_char_overflow(pager, ' ') ) + pager_push_newline(pager); + do + { + if ( pager_would_push_char_overflow(pager, ' ') ) + break; + pager->current_wcp.wcp_col++; + } while ( pager->current_wcp.wcp_col % 8 != 0 ); + } + else if ( wc == L'\r' ) + { + pager->current_wcp.wcp_col = 0; + } + else + { + if ( pager_would_push_char_overflow(pager, wc) ) + pager_push_newline(pager); + pager->current_wcp.wcp_col++; + } +} + +void pager_push_char(struct pager* pager, wchar_t wc) +{ + if ( wc < 32 && wc != L'\t' && wc != L'\n' ) + { + dprintf(pager->out_fd, "\e[97m"); + pager_push_char(pager, L'^'); + pager_push_char(pager, L'@' + wc); + dprintf(pager->out_fd, "\e[m"); + } + else + { + pager_push_final_char(pager, wc); + } +} + +void pager_push_byte(struct pager* pager, unsigned char byte) +{ + if ( pager->quiting ) + return; + + wchar_t wc; + size_t amount = mbrtowc(&wc, (const char*) &byte, 1, &pager->in_ps); + if ( amount == (size_t) -2 ) + return; + if ( amount == (size_t) -1 ) + { + wc = 0xFFFD /* REPLACEMENT CHARACTER */; + memset(&pager->in_ps, 0, sizeof(pager->in_ps)); + } + pager_push_char(pager, wc); +} + +void pager_simple_output_fd(struct pager* pager, int fd, const char* fdpath) +{ + unsigned char buffer[4096]; + ssize_t in_amount; + while ( 0 < (in_amount = read(fd, buffer, sizeof(buffer))) ) + { + if ( writeall(pager->out_fd, buffer, in_amount) < (size_t) in_amount ) + error(1, errno, ""); + } + if ( in_amount < 0 ) + error(1, errno, "%s", fdpath); +} + +void pager_push_fd(struct pager* pager, int fd, const char* fdpath) +{ + if ( pager->quiting ) + return; + + if ( !strcmp(fdpath, "") ) + pager->input_prompt_name = ""; + else + pager->input_prompt_name = fdpath; + // TODO: In this case, we should disable echoing and read from the terminal + // anyways. + if ( isatty(fd) ) + error(1, errno, "/dev/tty"); + if ( !pager->out_fd_tty ) + return pager_simple_output_fd(pager, fd, fdpath); + unsigned char buffer[4096]; + ssize_t in_amount; + while ( !pager->quiting && + 0 < (in_amount = read(fd, buffer, sizeof(buffer))) ) + { + for ( ssize_t i = 0; i < in_amount; i++ ) + pager_push_byte(pager, buffer[i]); + } + if ( in_amount < 0 ) + error(1, errno, "%s", fdpath); +} + +void pager_push_path(struct pager* pager, const char* path) +{ + if ( pager->quiting ) + return; + + if ( !strcmp(path, "-") ) + return pager_push_fd(pager, 0, ""); + int fd = open(path, O_RDONLY); + if ( fd < 0 ) + error(1, errno, "%s", path); + pager_push_fd(pager, fd, path); + close(fd); +} + +void compact_arguments(int* argc, char*** argv) +{ + for ( int i = 0; i < *argc; i++ ) + { + while ( i < *argc && !(*argv)[i] ) + { + for ( int n = i; n < *argc; n++ ) + (*argv)[n] = (*argv)[n+1]; + (*argc)--; + } + } +} + +void help(FILE* fp, const char* argv0) +{ + fprintf(fp, "Usage: %s [OPTION]... [FILES]...\n", argv0); + fprintf(fp, "Displays files one page at a time.\n"); +} + +void version(FILE* fp, const char* argv0) +{ + fprintf(fp, "%s (Sortix) %s\n", argv0, VERSIONSTR); + fprintf(fp, "License GPLv3+: GNU GPL version 3 or later .\n"); + fprintf(fp, "This is free software: you are free to change and redistribute it.\n"); + fprintf(fp, "There is NO WARRANTY, to the extent permitted by law.\n"); +} int main(int argc, char* argv[]) { - if ( isatty(0) && argc < 2 ) - { - printf("usage: %s [FILE] ...\n", argv[0]); - return 0; - } + setlocale(LC_ALL, ""); - if ( !isatty(0) && argc < 2 ) - { - stdinargv[0] = argv[0]; - stdinargv[1] = (char*) "-"; - argv = stdinargv; - argc = 2; - } - - int stdinfd = dup(0); - close(0); - int ttyfd = open("/dev/tty", O_RDONLY); - if ( ttyfd != 0 ) { perror("/dev/tty"); return 1; } - struct winsize ws; - if ( tcgetwinsize(0, &ws) ) - error(1, errno, "tcgetwinsize"); - const int HEIGHT = ws.ws_row; - const int WIDTH = ws.ws_col; - int linesleft = HEIGHT-1; - int result = 0; - size_t charleft = WIDTH; + const char* argv0 = argv[0]; for ( int i = 1; i < argc; i++ ) { - int fd = ( strcmp(argv[i], "-") == 0 ) ? stdinfd : open(argv[i], O_RDONLY); - if ( fd < 0 ) { result = 1; perror(argv[i]); continue; } - const size_t BUFFER_SIZE = 4096; - char buffer[BUFFER_SIZE]; - while ( true ) + const char* arg = argv[i]; + if ( arg[0] != '-' ) + continue; + argv[i] = NULL; + if ( !strcmp(arg, "--") ) + break; + if ( arg[1] != '-' ) { - ssize_t numbytes = read(fd, buffer, BUFFER_SIZE); - if ( !numbytes ) { break; } - if ( numbytes < 0 ) + while ( char c = *++arg ) switch ( c ) { - result = 1; - error(0, errno, "read: %s", argv[i]); - break; - } - for ( ssize_t i = 0; i < numbytes; i++ ) - { - char c = buffer[i]; - if ( c == '\n' ) { charleft = WIDTH; } - bool eol = (c == '\n') || !charleft; - if ( eol ) { charleft = WIDTH; } - if ( eol && linesleft <= 1 ) - { - printf("\n--pager--"); - fflush(stdout); - settermmode(0, TERMMODE_KBKEY | TERMMODE_SIGNAL); - bool doexit = false; - int kbkey; - do - { - uint32_t codepoint; - ssize_t numbytes = read(0, &codepoint, sizeof(codepoint)); - if ( !numbytes ) { exit(0); } - if ( numbytes < 0 ) { error(1, errno, "read(stdin)"); } - if ( numbytes < (ssize_t) sizeof(codepoint) ) { error(1, errno, "bad stdin"); } - if ( !(kbkey = KBKEY_DECODE(codepoint)) ) { continue; } - if ( kbkey == KBKEY_DOWN ) { break; } - if ( kbkey == KBKEY_PGDOWN ) { linesleft = HEIGHT-1; break; } - if ( kbkey == -KBKEY_Q ) { doexit = true; break; } - } while ( kbkey != KBKEY_ENTER ); - printf("\r\e[J"); - if ( doexit ) { exit(result); } - continue; - } - if ( eol && linesleft ) { linesleft--; } - printf("%c", c); - charleft--; - if ( c == '\t' ) { charleft &= ~(8-1); } + default: + fprintf(stderr, "%s: unknown option -- '%c'\n", argv0, c); + help(stderr, argv0); + exit(1); } } - if ( fd != stdinfd ) { close(fd); } + else if ( !strcmp(arg, "--help") ) + help(stdout, argv0), exit(0); + else if ( !strcmp(arg, "--version") ) + version(stdout, argv0), exit(0); + else + { + fprintf(stderr, "%s: unknown option: %s\n", argv0, arg); + help(stderr, argv0); + exit(1); + } } - return result; + + compact_arguments(&argc, &argv); + + struct pager pager; + memset(&pager, 0, sizeof(pager)); + pager_init(&pager); + + if ( argc == 1 ) + { + if ( pager.tty_fd == 0 ) + error(1, 0, "missing file operand"); + pager_push_fd(&pager, 0, ""); + } + else for ( int i = 1; i < argc; i++ ) + { + pager_push_path(&pager, argv[i]); + } + + return 0; }