projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| 92b4044d C |
1 | /* cons.c 1.2 89/04/25 */ |
| 2 | ||
| 3 | /* | |
| 4 | * Asynchronous versions of getchar and gets | |
| 5 | * for use in disk formatter. | |
| 6 | */ | |
| 7 | #include "machine/mtpr.h" | |
| 8 | ||
| 9 | #include "param.h" | |
| 10 | #include "../tahoe/cp.h" | |
| 11 | ||
| 12 | int wait_for_char = 1; /* synchronous by default */ | |
| 13 | extern struct cpdcb_i cpin; /* in ../prf.c */ | |
| 14 | ||
| 15 | agetchar() | |
| 16 | { | |
| 17 | static char_read = 0; /* read operation pending */ | |
| 18 | char c; | |
| 19 | ||
| 20 | if (!char_read) { | |
| 21 | char_read = 1; | |
| 22 | cpin.cp_hdr.cp_unit = CPCONS; /* Resets done bit */ | |
| 23 | cpin.cp_hdr.cp_comm = CPREAD; | |
| 24 | cpin.cp_hdr.cp_count = 1; | |
| 25 | mtpr(CPMDCB, &cpin); | |
| 26 | } | |
| 27 | uncache(&cpin.cp_hdr.cp_unit); | |
| 28 | if (wait_for_char) { | |
| 29 | while ((cpin.cp_hdr.cp_unit & CPDONE) == 0) | |
| 30 | uncache(&cpin.cp_hdr.cp_unit); | |
| 31 | } else | |
| 32 | if ((cpin.cp_hdr.cp_unit & CPDONE) == 0) | |
| 33 | return (0); | |
| 34 | uncache(&cpin.cpi_buf[0]); | |
| 35 | c = cpin.cpi_buf[0] & 0x7f; | |
| 36 | char_read = 0; | |
| 37 | if (c == '\r') | |
| 38 | c = '\n'; | |
| 39 | if (c != '\b' && c != '\177') | |
| 40 | putchar(c); | |
| 41 | return (c); | |
| 42 | } | |
| 43 | ||
| 44 | agets(buf) | |
| 45 | char *buf; | |
| 46 | { | |
| 47 | static char line[256]; | |
| 48 | static char *lp = line; | |
| 49 | register c; | |
| 50 | ||
| 51 | *buf = '\0'; | |
| 52 | for (;;) { | |
| 53 | c = agetchar() & 0177; | |
| 54 | switch(c) { | |
| 55 | case '\0' : | |
| 56 | if (!wait_for_char) | |
| 57 | return; | |
| 58 | break; | |
| 59 | case '\n': | |
| 60 | case '\r': | |
| 61 | c = '\n'; | |
| 62 | *lp = '\0'; | |
| 63 | strcpy(buf, line); | |
| 64 | lp = line; | |
| 65 | return; | |
| 66 | case '\b': | |
| 67 | case '\177': | |
| 68 | if (lp > line) { | |
| 69 | lp--; | |
| 70 | putchar('\b'); | |
| 71 | putchar(' '); | |
| 72 | putchar('\b'); | |
| 73 | } | |
| 74 | continue; | |
| 75 | case '#': | |
| 76 | lp--; | |
| 77 | if (lp < line) | |
| 78 | lp = line; | |
| 79 | continue; | |
| 80 | case '@': | |
| 81 | case 'u'&037: | |
| 82 | lp = line; | |
| 83 | putchar('\n'); | |
| 84 | continue; | |
| 85 | default: | |
| 86 | if ((lp - line) < 256) | |
| 87 | *lp++ = c; | |
| 88 | } | |
| 89 | } | |
| 90 | } |