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author | Lorry Tar Creator <lorry-tar-importer@baserock.org> | 2012-07-21 20:40:00 +0000 |
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committer | Lorry <lorry@roadtrain.codethink.co.uk> | 2012-09-24 16:52:48 +0000 |
commit | 09a405d8f652b56944c93ebf5c673cdfe5319b04 (patch) | |
tree | 9cc4518b0a21096735b20ac3204a6fa032f1c566 /prompt.c | |
download | less-master.tar.gz |
Imported from /srv/lorry/lorry-area/less/less-451.tar.gz.HEADless-451masterbaserock/morph
Diffstat (limited to 'prompt.c')
-rwxr-xr-x | prompt.c | 586 |
1 files changed, 586 insertions, 0 deletions
diff --git a/prompt.c b/prompt.c new file mode 100755 index 0000000..f374101 --- /dev/null +++ b/prompt.c @@ -0,0 +1,586 @@ +/* + * Copyright (C) 1984-2012 Mark Nudelman + * + * You may distribute under the terms of either the GNU General Public + * License or the Less License, as specified in the README file. + * + * For more information, see the README file. + */ + + +/* + * Prompting and other messages. + * There are three flavors of prompts, SHORT, MEDIUM and LONG, + * selected by the -m/-M options. + * There is also the "equals message", printed by the = command. + * A prompt is a message composed of various pieces, such as the + * name of the file being viewed, the percentage into the file, etc. + */ + +#include "less.h" +#include "position.h" + +extern int pr_type; +extern int new_file; +extern int sc_width; +extern int so_s_width, so_e_width; +extern int linenums; +extern int hshift; +extern int sc_height; +extern int jump_sline; +extern int less_is_more; +extern IFILE curr_ifile; +#if EDITOR +extern char *editor; +extern char *editproto; +#endif + +/* + * Prototypes for the three flavors of prompts. + * These strings are expanded by pr_expand(). + */ +static constant char s_proto[] = + "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x..%t"; +static constant char m_proto[] = + "?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t"; +static constant char M_proto[] = + "?f%f .?n?m(%T %i of %m) ..?ltlines %lt-%lb?L/%L. :byte %bB?s/%s. .?e(END) ?x- Next\\: %x.:?pB%pB\\%..%t"; +static constant char e_proto[] = + "?f%f .?m(%T %i of %m) .?ltlines %lt-%lb?L/%L. .byte %bB?s/%s. ?e(END) :?pB%pB\\%..%t"; +static constant char h_proto[] = + "HELP -- ?eEND -- Press g to see it again:Press RETURN for more., or q when done"; +static constant char w_proto[] = + "Waiting for data"; +static constant char more_proto[] = + "--More--(?eEND ?x- Next\\: %x.:?pB%pB\\%:byte %bB?s/%s...%t)"; + +public char *prproto[3]; +public char constant *eqproto = e_proto; +public char constant *hproto = h_proto; +public char constant *wproto = w_proto; + +static char message[PROMPT_SIZE]; +static char *mp; + +/* + * Initialize the prompt prototype strings. + */ + public void +init_prompt() +{ + prproto[0] = save(s_proto); + prproto[1] = save(less_is_more ? more_proto : m_proto); + prproto[2] = save(M_proto); + eqproto = save(e_proto); + hproto = save(h_proto); + wproto = save(w_proto); +} + +/* + * Append a string to the end of the message. + */ + static void +ap_str(s) + char *s; +{ + int len; + + len = strlen(s); + if (mp + len >= message + PROMPT_SIZE) + len = message + PROMPT_SIZE - mp - 1; + strncpy(mp, s, len); + mp += len; + *mp = '\0'; +} + +/* + * Append a character to the end of the message. + */ + static void +ap_char(c) + char c; +{ + char buf[2]; + + buf[0] = c; + buf[1] = '\0'; + ap_str(buf); +} + +/* + * Append a POSITION (as a decimal integer) to the end of the message. + */ + static void +ap_pos(pos) + POSITION pos; +{ + char buf[INT_STRLEN_BOUND(pos) + 2]; + + postoa(pos, buf); + ap_str(buf); +} + +/* + * Append a line number to the end of the message. + */ + static void +ap_linenum(linenum) + LINENUM linenum; +{ + char buf[INT_STRLEN_BOUND(linenum) + 2]; + + linenumtoa(linenum, buf); + ap_str(buf); +} + +/* + * Append an integer to the end of the message. + */ + static void +ap_int(num) + int num; +{ + char buf[INT_STRLEN_BOUND(num) + 2]; + + inttoa(num, buf); + ap_str(buf); +} + +/* + * Append a question mark to the end of the message. + */ + static void +ap_quest() +{ + ap_str("?"); +} + +/* + * Return the "current" byte offset in the file. + */ + static POSITION +curr_byte(where) + int where; +{ + POSITION pos; + + pos = position(where); + while (pos == NULL_POSITION && where >= 0 && where < sc_height-1) + pos = position(++where); + if (pos == NULL_POSITION) + pos = ch_length(); + return (pos); +} + +/* + * Return the value of a prototype conditional. + * A prototype string may include conditionals which consist of a + * question mark followed by a single letter. + * Here we decode that letter and return the appropriate boolean value. + */ + static int +cond(c, where) + char c; + int where; +{ + POSITION len; + + switch (c) + { + case 'a': /* Anything in the message yet? */ + return (mp > message); + case 'b': /* Current byte offset known? */ + return (curr_byte(where) != NULL_POSITION); + case 'c': + return (hshift != 0); + case 'e': /* At end of file? */ + return (eof_displayed()); + case 'f': /* Filename known? */ + return (strcmp(get_filename(curr_ifile), "-") != 0); + case 'l': /* Line number known? */ + case 'd': /* Same as l */ + return (linenums); + case 'L': /* Final line number known? */ + case 'D': /* Final page number known? */ + return (linenums && ch_length() != NULL_POSITION); + case 'm': /* More than one file? */ +#if TAGS + return (ntags() ? (ntags() > 1) : (nifile() > 1)); +#else + return (nifile() > 1); +#endif + case 'n': /* First prompt in a new file? */ +#if TAGS + return (ntags() ? 1 : new_file); +#else + return (new_file); +#endif + case 'p': /* Percent into file (bytes) known? */ + return (curr_byte(where) != NULL_POSITION && + ch_length() > 0); + case 'P': /* Percent into file (lines) known? */ + return (currline(where) != 0 && + (len = ch_length()) > 0 && + find_linenum(len) != 0); + case 's': /* Size of file known? */ + case 'B': + return (ch_length() != NULL_POSITION); + case 'x': /* Is there a "next" file? */ +#if TAGS + if (ntags()) + return (0); +#endif + return (next_ifile(curr_ifile) != NULL_IFILE); + } + return (0); +} + +/* + * Decode a "percent" prototype character. + * A prototype string may include various "percent" escapes; + * that is, a percent sign followed by a single letter. + * Here we decode that letter and take the appropriate action, + * usually by appending something to the message being built. + */ + static void +protochar(c, where, iseditproto) + int c; + int where; + int iseditproto; +{ + POSITION pos; + POSITION len; + int n; + LINENUM linenum; + LINENUM last_linenum; + IFILE h; + +#undef PAGE_NUM +#define PAGE_NUM(linenum) ((((linenum) - 1) / (sc_height - 1)) + 1) + + switch (c) + { + case 'b': /* Current byte offset */ + pos = curr_byte(where); + if (pos != NULL_POSITION) + ap_pos(pos); + else + ap_quest(); + break; + case 'c': + ap_int(hshift); + break; + case 'd': /* Current page number */ + linenum = currline(where); + if (linenum > 0 && sc_height > 1) + ap_linenum(PAGE_NUM(linenum)); + else + ap_quest(); + break; + case 'D': /* Final page number */ + /* Find the page number of the last byte in the file (len-1). */ + len = ch_length(); + if (len == NULL_POSITION) + ap_quest(); + else if (len == 0) + /* An empty file has no pages. */ + ap_linenum(0); + else + { + linenum = find_linenum(len - 1); + if (linenum <= 0) + ap_quest(); + else + ap_linenum(PAGE_NUM(linenum)); + } + break; +#if EDITOR + case 'E': /* Editor name */ + ap_str(editor); + break; +#endif + case 'f': /* File name */ + ap_str(get_filename(curr_ifile)); + break; + case 'F': /* Last component of file name */ + ap_str(last_component(get_filename(curr_ifile))); + break; + case 'i': /* Index into list of files */ +#if TAGS + if (ntags()) + ap_int(curr_tag()); + else +#endif + ap_int(get_index(curr_ifile)); + break; + case 'l': /* Current line number */ + linenum = currline(where); + if (linenum != 0) + ap_linenum(linenum); + else + ap_quest(); + break; + case 'L': /* Final line number */ + len = ch_length(); + if (len == NULL_POSITION || len == ch_zero() || + (linenum = find_linenum(len)) <= 0) + ap_quest(); + else + ap_linenum(linenum-1); + break; + case 'm': /* Number of files */ +#if TAGS + n = ntags(); + if (n) + ap_int(n); + else +#endif + ap_int(nifile()); + break; + case 'p': /* Percent into file (bytes) */ + pos = curr_byte(where); + len = ch_length(); + if (pos != NULL_POSITION && len > 0) + ap_int(percentage(pos,len)); + else + ap_quest(); + break; + case 'P': /* Percent into file (lines) */ + linenum = currline(where); + if (linenum == 0 || + (len = ch_length()) == NULL_POSITION || len == ch_zero() || + (last_linenum = find_linenum(len)) <= 0) + ap_quest(); + else + ap_int(percentage(linenum, last_linenum)); + break; + case 's': /* Size of file */ + case 'B': + len = ch_length(); + if (len != NULL_POSITION) + ap_pos(len); + else + ap_quest(); + break; + case 't': /* Truncate trailing spaces in the message */ + while (mp > message && mp[-1] == ' ') + mp--; + *mp = '\0'; + break; + case 'T': /* Type of list */ +#if TAGS + if (ntags()) + ap_str("tag"); + else +#endif + ap_str("file"); + break; + case 'x': /* Name of next file */ + h = next_ifile(curr_ifile); + if (h != NULL_IFILE) + ap_str(get_filename(h)); + else + ap_quest(); + break; + } +} + +/* + * Skip a false conditional. + * When a false condition is found (either a false IF or the ELSE part + * of a true IF), this routine scans the prototype string to decide + * where to resume parsing the string. + * We must keep track of nested IFs and skip them properly. + */ + static constant char * +skipcond(p) + register constant char *p; +{ + register int iflevel; + + /* + * We came in here after processing a ? or :, + * so we start nested one level deep. + */ + iflevel = 1; + + for (;;) switch (*++p) + { + case '?': + /* + * Start of a nested IF. + */ + iflevel++; + break; + case ':': + /* + * Else. + * If this matches the IF we came in here with, + * then we're done. + */ + if (iflevel == 1) + return (p); + break; + case '.': + /* + * Endif. + * If this matches the IF we came in here with, + * then we're done. + */ + if (--iflevel == 0) + return (p); + break; + case '\\': + /* + * Backslash escapes the next character. + */ + ++p; + break; + case '\0': + /* + * Whoops. Hit end of string. + * This is a malformed conditional, but just treat it + * as if all active conditionals ends here. + */ + return (p-1); + } + /*NOTREACHED*/ +} + +/* + * Decode a char that represents a position on the screen. + */ + static constant char * +wherechar(p, wp) + char constant *p; + int *wp; +{ + switch (*p) + { + case 'b': case 'd': case 'l': case 'p': case 'P': + switch (*++p) + { + case 't': *wp = TOP; break; + case 'm': *wp = MIDDLE; break; + case 'b': *wp = BOTTOM; break; + case 'B': *wp = BOTTOM_PLUS_ONE; break; + case 'j': *wp = adjsline(jump_sline); break; + default: *wp = TOP; p--; break; + } + } + return (p); +} + +/* + * Construct a message based on a prototype string. + */ + public char * +pr_expand(proto, maxwidth) + constant char *proto; + int maxwidth; +{ + register constant char *p; + register int c; + int where; + + mp = message; + + if (*proto == '\0') + return (""); + + for (p = proto; *p != '\0'; p++) + { + switch (*p) + { + default: /* Just put the character in the message */ + ap_char(*p); + break; + case '\\': /* Backslash escapes the next character */ + p++; + ap_char(*p); + break; + case '?': /* Conditional (IF) */ + if ((c = *++p) == '\0') + --p; + else + { + where = 0; + p = wherechar(p, &where); + if (!cond(c, where)) + p = skipcond(p); + } + break; + case ':': /* ELSE */ + p = skipcond(p); + break; + case '.': /* ENDIF */ + break; + case '%': /* Percent escape */ + if ((c = *++p) == '\0') + --p; + else + { + where = 0; + p = wherechar(p, &where); + protochar(c, where, +#if EDITOR + (proto == editproto)); +#else + 0); +#endif + + } + break; + } + } + + if (mp == message) + return (""); + if (maxwidth > 0 && mp >= message + maxwidth) + { + /* + * Message is too long. + * Return just the final portion of it. + */ + return (mp - maxwidth); + } + return (message); +} + +/* + * Return a message suitable for printing by the "=" command. + */ + public char * +eq_message() +{ + return (pr_expand(eqproto, 0)); +} + +/* + * Return a prompt. + * This depends on the prompt type (SHORT, MEDIUM, LONG), etc. + * If we can't come up with an appropriate prompt, return NULL + * and the caller will prompt with a colon. + */ + public char * +pr_string() +{ + char *prompt; + int type; + + type = (!less_is_more) ? pr_type : pr_type ? 0 : 1; + prompt = pr_expand((ch_getflags() & CH_HELPFILE) ? + hproto : prproto[type], + sc_width-so_s_width-so_e_width-2); + new_file = 0; + return (prompt); +} + +/* + * Return a message suitable for printing while waiting in the F command. + */ + public char * +wait_message() +{ + return (pr_expand(wproto, sc_width-so_s_width-so_e_width-2)); +} |