1 /* src/common/readwrite.c */
4 #include <stddef.h> /* size_t */
5 #include <stdint.h> /* uint8_t, uint16_t, uint32_t, UINT32_MAX */
6 #include <stdio.h> /* FILE, fseek(), sprintf(), fgets(), fgetc(), ferror(),
7 * fputc(), fwrite(), fclose(), fopen(), clearerr()
9 #include <stdlib.h> /* free() */
10 #include <string.h> /* strlen() */
11 #include <unistd.h> /* access(), unlink() */
12 #include "rexit.h" /* exit_err(), exit_trouble() */
13 #include "try_malloc.h" /* try_malloc() */
17 extern FILE * try_fopen(char * path, char * mode, const char * f)
19 char * msg1 = "Trouble in ";
20 char * msg2 = " with fopen (mode '";
21 char * msg3 = "') on path '";
23 uint16_t size = strlen(msg1) + strlen(msg2) + strlen(msg3) + strlen(msg4)
24 + strlen(f) + strlen(path) + strlen(mode) + 1;
25 char * msg = try_malloc(size, __func__);
26 int test = sprintf(msg, "%s%s%s%s%s%s%s", msg1,f,msg2,mode,msg3,path,msg4);
27 exit_trouble(test < 0, __func__, "sprintf");
28 FILE * file_p = fopen(path, mode);
29 exit_err(!file_p, msg);
36 extern void try_fclose(FILE * file, const char * f)
38 exit_trouble(fclose(file), f, "fclose");
43 extern void try_fwrite(void * ptr, size_t size, size_t nmemb, FILE * stream,
46 exit_trouble(0 == fwrite(ptr, size, nmemb, stream), f, "fwrite");
51 extern void try_fputc(uint8_t c, FILE * file, const char * f)
53 exit_trouble(EOF == fputc(c, file), f, "fputc");
58 extern int try_fgetc(FILE * file, const char * f)
60 clearerr(file); /* OSX' (BSD?) fgetc() needs this to undo previous EOFs. */
61 int test = fgetc(file);
62 exit_trouble(EOF == test && ferror(file), f, "fgetc");
68 extern char * try_fgets(char * line, int linemax, FILE * file, const char * f)
70 char * test = fgets(line, linemax, file);
71 exit_trouble(!test && ferror(file), f, "fgets");
77 extern char * build_temp_path(char * path)
79 char * suffix_tmp = "_tmp";
80 uint16_t size = strlen(path) + strlen(suffix_tmp) + 1;
81 char * path_tmp = try_malloc(size, __func__);
82 int test = sprintf(path_tmp, "%s%s", path, suffix_tmp);
83 exit_trouble(test < 0, __func__, "sprintf");
89 extern FILE * atomic_write_start(char * path, char ** path_tmp)
91 *path_tmp = build_temp_path(path);
92 return try_fopen(*path_tmp, "w", __func__);
97 extern void atomic_write_finish(FILE * file, char * path, char * path_tmp)
99 try_fclose(file, __func__);
100 char * msg1 = "Trouble in ";
102 if (!access(path, F_OK))
104 char * msg2 = " with unlink on path '";
105 uint16_t size = strlen(msg1) + strlen(msg2) + strlen(msg4)
106 + strlen(__func__) + strlen(path) + 1;
107 char * msg = try_malloc(size, __func__);
108 int test = sprintf(msg, "%s%s%s%s%s", msg1, __func__, msg2, path, msg4);
109 exit_trouble(test < 0, __func__, "sprintf");
110 exit_err(unlink(path), msg);
113 char * msg2 = " with rename from '";
114 char * msg3 = "' to '";
115 uint16_t size = strlen(msg1) + strlen(__func__) + strlen(msg2) +
116 + strlen(path_tmp) + strlen(msg3) + strlen(path)
118 char * msg = try_malloc(size, __func__);
119 int test = sprintf(msg, "%s%s%s%s%s%s%s",
120 msg1, __func__, msg2, path_tmp, msg3, path, msg4);
121 exit_trouble(test < 0, __func__, "sprintf");
122 exit_err(rename(path_tmp, path), msg);
129 extern void detect_atomic_leftover(char * path)
131 char * path_tmp = build_temp_path(path);
132 char * part1 = "Found file '";
133 char * part2 = "' that may be a leftover from an aborted previous attempt "
135 char * part3 = "'. Aborting until the matter is solved by (re-)moving it.";
136 uint32_t size = strlen(part1) + strlen(path_tmp) + strlen(part2)
137 + strlen(path) + strlen(part3) + 1;
138 char * msg = try_malloc(size, __func__);
139 int test = sprintf(msg, "%s%s%s%s%s", part1, path_tmp, part2, path, part3);
140 exit_trouble(test < 0, __func__, "sprintf");
141 exit_err(!access(path_tmp, F_OK), msg);
148 extern uint32_t textfile_width(FILE * file)
151 uint32_t c_count = 0;
152 uint32_t linemax = 0;
155 c = try_fgetc(file, __func__);
161 exit_trouble(UINT32_MAX==c_count, __func__, "too large text file line");
164 if (c_count > linemax)
171 if (0 == linemax && 0 < c_count) /* Handle files that consist of only one */
172 { /* line / lack newline chars. */
175 exit_trouble(-1 == fseek(file, 0, SEEK_SET), __func__, "fseek");