X-Git-Url: https://plomlompom.com/repos/?a=blobdiff_plain;f=src%2Freadwrite.c;h=09faaeb282dcb8a84731c5c1bce3c69b2dd41c77;hb=550d22ec0c3f530f5d317746f3f7e75251a1de4b;hp=8afcfb59bf204bfbb0fafb5b765c57488af25ac9;hpb=84fec7f904ee0951c85803071b53002b6bd6e93b;p=plomrogue diff --git a/src/readwrite.c b/src/readwrite.c index 8afcfb5..09faaeb 100644 --- a/src/readwrite.c +++ b/src/readwrite.c @@ -1,37 +1,248 @@ -/* readwrite.c */ +/* readwrite.c */ #include "readwrite.h" -#include -#include +#include /* for FILE typedef, fopen(), fgetc(), fputc(), fseek(), + * sprintf(), fwrite() + */ +#include /* for uint8_t, uint16_t, uint32_t */ +#include /* for strlen()*/ +#include /* for unlink() */ +#include "rexit.h" /* for exit_err() */ +#include "misc.h" /* for trouble_msg() */ +struct World; -extern uint16_t read_uint16_bigendian( FILE * file ) + + +/* Read/write "x" from/to "file" as bigendian representation of "size" bits. On + * failure, return 1, else 0. (As of of now, all extern read/write functions + * build on top of these.) + * + * Only use multiples of 8 greater or equal 32 for "size", so that storage + * inside uint32_t is possible. Originally a bit number check prefaced the code + * of both functions. It was removed as redundant due to all possible "size" + * values being hardcoded into the library (i.e. in all extern functions calling + * / wrapping around either function). If this ever changes, (re-)insert: + * + * if (0 == size || size > 32 || 0 != size % 8) + * { + * return 1; + * } + */ +static uint8_t read_uintX_bigendian(FILE * file, uint32_t * x, uint8_t size); +static uint8_t write_uintX_bigendian(FILE * file, uint32_t x, uint8_t size); + + + +extern FILE * try_fopen(char * path, char * mode, struct World * w, char * f) +{ + char * msg1 = "Trouble in "; + char * msg2 = " with fopen() (mode '"; + char * msg3 = "') on path '"; + char * msg4 = "'."; + uint16_t size = strlen(msg1) + strlen(msg2) + strlen(msg3) + strlen(msg4) + + strlen(f) + strlen(path) + strlen(mode) + 1; + char msg[size]; + sprintf(msg, "%s%s%s%s%s%s%s", msg1, f, msg2, mode, msg3, path, msg4); + FILE * file_p = fopen(path, mode); + exit_err(NULL == file_p, w, msg); + return file_p; +} + + + +extern void try_fclose(FILE * file, struct World * w, char * f) +{ + char * msg = trouble_msg(w, f, "fclose()"); + exit_err(fclose(file), w, msg); + free(msg); +} + + + +extern void try_fgets(char * line, int linemax, FILE * file, + struct World * w, char * f) +{ + char * msg = trouble_msg(w, f, "fgets()"); + exit_err(NULL == fgets(line, linemax, file), w, msg); + free(msg); +} + + + +extern void try_fwrite(void * ptr, size_t size, size_t nmemb, FILE * stream, + struct World * w, char * f) { - uint16_t x; - x = (uint16_t) fgetc(file) << 8 ; - x = x + (uint16_t) fgetc(file) ; - return x; + char * msg = trouble_msg(w, f, "fwrite()"); + exit_err(0 == fwrite(ptr, size, nmemb, stream), w, msg); + free(msg); } -extern uint32_t read_uint32_bigendian( FILE * file ) + + +extern void try_fclose_unlink_rename(FILE * file, char * p1, char * p2, + struct World * w, char * f) { - uint32_t x; - x = (uint32_t) fgetc(file) << 24 ; - x = x + ( (uint32_t) fgetc(file) << 16 ) ; - x = x + ( (uint32_t) fgetc(file) << 8 ) ; - x = x + (uint32_t) fgetc(file) ; - return x; + try_fclose(file, w, f); + char * msg1 = "Trouble in "; + char * msg4 = "'."; + if (!access(p2, F_OK)) + { + char * msg2 = " with unlink() on path '"; + uint16_t size = strlen(msg1) + strlen(msg2) + strlen(msg4) + + strlen(f) + strlen(p2) + 1; + char msg[size]; + sprintf(msg, "%s%s%s%s%s", msg1, f, msg2, p2, msg4); + exit_err(unlink(p2), w, msg); + } + char * msg2 = " with rename() from '"; + char * msg3 = "' to '"; + uint16_t size = strlen(msg1) + strlen(f) + strlen(msg2) + strlen(p1) + + strlen(msg3) + strlen(p2) + strlen(msg4) + 1; + char msg[size]; + sprintf(msg, "%s%s%s%s%s%s%s", msg1, f, msg2, p1, msg3, p2, msg4); + exit_err(rename(p1, p2), w, msg); } -extern void write_uint16_bigendian( uint16_t x, FILE * file ) + + +extern uint16_t get_linemax(FILE * file, struct World * w, char * f) { - fputc( x >> 8, file ); - fputc( x & 0xFF, file ); + char * msg = trouble_msg(w, f, "textfile_sizes()"); + uint16_t linemax; + exit_err(textfile_sizes(file, &linemax, NULL), w, msg); + free(msg); + return linemax; } -extern void write_uint32_bigendian( uint32_t x, FILE * file ) + + +extern uint8_t textfile_sizes(FILE * file, uint16_t * linemax_p, + uint16_t * n_lines_p) +{ + int c = 0; + uint16_t c_count = 0; + uint16_t n_lines = 0; + uint16_t linemax = 0; + while (1) + { + c = fgetc(file); + if (EOF == c) + { + break; + } + c_count++; + if ('\n' == c) + { + if (c_count > linemax) + { + linemax = c_count; + } + c_count = 0; + if (n_lines_p) + { + n_lines++; + } + } + } + if (0 == linemax && 0 < c_count) /* Handle files that consist of only one */ + { /* line / lack newline chars. */ + linemax = c_count; + } + + if (-1 == fseek(file, 0, SEEK_SET)) + { + return 1; + } + * linemax_p = linemax; + if (n_lines_p) + { + * n_lines_p = n_lines; + } + return 0; +} + + + +static uint8_t read_uintX_bigendian(FILE * file, uint32_t * x, uint8_t size) +{ + * x = 0; + int16_t bitshift = size - 8; + int test; + for (; bitshift >= 0; bitshift = bitshift - 8) + { + test = fgetc(file); + if (EOF == test) + { + return 1; + } + * x = * x + ((uint32_t) test << bitshift); + } + return 0; +} + + + +static uint8_t write_uintX_bigendian(FILE * file, uint32_t x, uint8_t size) +{ + int16_t bitshift = size - 8; + for (; bitshift >= 0; bitshift = bitshift - 8) + { + if (EOF == fputc((x >> bitshift) & 0xFF, file)) + { + return 1; + } + } + return 0; +} + + + +extern uint8_t read_uint8(FILE * file, uint8_t * x) +{ + /* Since read_uintX_bigendian() works on -- and zeroes -- four bytes, direct + * work on values of fewer bytes would corrupt immediate neighbor values. + */ + uint32_t y = * x; + uint8_t err = read_uintX_bigendian(file, &y, 8); + * x = (uint8_t) y; + return err; +} + + + +extern uint8_t read_uint16_bigendian(FILE * file, uint16_t * x) +{ + /* See read_uint8() introductory code comment for rationale. */ + uint32_t y = * x; + uint8_t err = read_uintX_bigendian(file, &y, 16); + * x = (uint16_t) y; + return err; +} + + + +extern uint8_t read_uint32_bigendian(FILE * file, uint32_t * x) +{ + return read_uintX_bigendian(file, x, 32); +} + + + +extern uint8_t write_uint8(uint8_t x, FILE * file) +{ + return write_uintX_bigendian(file, x, 8); +} + + + +extern uint8_t write_uint16_bigendian(uint16_t x, FILE * file) +{ + return write_uintX_bigendian(file, x, 16); +} + + + +extern uint8_t write_uint32_bigendian(uint32_t x, FILE * file) { - fputc( ( x >> 24 ) & 0xFF, file); - fputc( ( x >> 16 ) & 0xFF, file); - fputc( ( x >> 8 ) & 0xFF, file); - fputc( x & 0xFF, file); + return write_uintX_bigendian(file, x, 32); }